PPOP Component

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The PPOP component is used retrieve and process OpenPGP encrypted and/or signed messages from Internet Post Office servers (POP).

Syntax

TipgPPOP

Remarks

The PPOP component implements a standard internet post office (POP3) client, as specified in RFC 1725, and supports decrypting and verifying signatures of encrypted and signed emails using OpenPGP. You can send an OpenPGP signed and encrypted message using the PSMTP component by calling the Encrypt, Sign, and SignAndEncrypt methods.

Connect to the Server

To connect to a MailServer, first set the appropriate User and Password and then connect by calling the Connect method. Upon successful connection to the MailServer, the number of waiting messages is shown by the MessageCount property. A message is selected by setting the MessageNumber property to a number between 1 and MessageCount (inclusive). Then, the message text and/or headers are received by calling the Retrieve method.

Receive Messages

The message text is received through the Transfer event, whereas the message headers are received through the Header event. Additionally, up to MaxLines from the message body are provided in the MessageText property. The StartTransfer and EndTransfer events are fired at the beginning and end of message transmission. The PITrail event provides a trace of the interaction between the client and server (excluding message transfers).

Verify

To verify the signature of a message specify the public key to be used for signature verification by setting the SignerKey* properties. For instance: PPOP1.SignerKeyCount = 1 PPOP1.SignerKeyKeyring(0) = "c:\my_keyring_dir" PPOP1.SignerKeyUserId(0) = "sender@nsoftware.com" The specified public key will be used to verify the signature when calling VerifySignature.

Decrypt

To process an encrypted or signed message first retrieve the message text and headers by calling Retrieve. To decrypt a message specify the private key to be used for decryption by setting the Key* properties. For instance: PPOP1.KeyCount = 1 PPOP1.KeyKeyring(0) = "c:\my_keyring_dir" PPOP1.KeyUserId(0) = "recipient@nsoftware.com" PPOP1.KeyPassphrase(0) = "password" The specified private key will be used to decrypt the message when calling Decrypt.

Decrypt and Verify

To decrypt and verify in one step, you can call DecryptAndVerifySignature. Set the public key of the sender in the and the private key to be used for decryption in the Key* properties .

Property List

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

Method List

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

Event List

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

Config Settings

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

AuthMechanism Property (PPOP Component)

This property includes the authentication mechanism to be used when connecting to the mail server.

Syntax

property AuthMechanism: TipgTAuthMechanisms read get_AuthMechanism write set_AuthMechanism;

TipgTAuthMechanisms = (
  amUserPassword,
  amCRAMMD5,
  amNTLM,
  amAPOP,
  amSASLPlain,
  amSASLDigestMD5,
  amKerberos,
  amXOAUTH2
);

Default Value

amUserPassword

Remarks

This property is used as the authentication mechanism when connecting to the mail server. By default, this property is amUserPassword (0), and default plaintext authentication is used to log in to the server. Other, more secure, options include amCRAMMD5 (1) for CRAM-MD5, amNTLM (2) for NTLM authentication, amAPOP (3) for APOP authentication, and amSASLDigestMD5 (5) for SASL DIGEST-MD5 authentication.

amSASLPlain (4) is also available, but most servers require a Secure Sockets Layer (SSL) connection when utilizing this authentication mechanism.

amKerberos (6) is for Kerberos authentication. Note: This functionality is available only in Windows.

Connected Property (PPOP Component)

Whether the component is connected.

Syntax

property Connected: Boolean read get_Connected;

Default Value

false

Remarks

This property is used to determine whether or not the component is connected to the remote host. Use the Connect and Disconnect methods to manage the connection.

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

Firewall Property (PPOP Component)

A set of properties related to firewall access.

Syntax

property Firewall: TipgFirewall read get_Firewall write set_Firewall;

Remarks

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

Idle Property (PPOP Component)

The current status of the component.

Syntax

property Idle: Boolean read get_Idle;

Default Value

true

Remarks

This property will be False if the component is currently busy (communicating or waiting for an answer), and True at all other times.

This property is read-only.

IncludeHeaders Property (PPOP Component)

This property instructs the component to include the headers in the MessageText and LocalFile.

Syntax

property IncludeHeaders: Boolean read get_IncludeHeaders write set_IncludeHeaders;

Default Value

false

Remarks

This property instructs the component to include the headers in the MessageText and LocalFile. If set to True, the headers for the message being retrieved will be placed before the message body in the MessageText property;. If LocalFile is set, then the headers will be written to that file before the message body. In this manner, the whole content of a MIME-encoded message can be passed to the MIME component for further message processing.

Keys Property (PPOP Component)

A collection of keys used for cryptographic operations.

Syntax

property Keys: TipgKeyList read get_Keys write set_Keys;

Remarks

This collection holds keys that are used for signing and decrypting. In most cases only one key will be specified, however multiple keys may be needed in some cases.

This property is not available at design time.

LastReply Property (PPOP Component)

This property indicates the last reply received from the server.

Syntax

property LastReply: String read get_LastReply;

Default Value

''

Remarks

This property indicates the last reply received from the server. It can be used for informational purposes. The same information and more also can be retrieved through the PITrail event.

This property is read-only.

LocalHost Property (PPOP Component)

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

Syntax

property LocalHost: String read get_LocalHost write set_LocalHost;

Default Value

''

Remarks

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

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

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

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

MailPort Property (PPOP Component)

This property includes the server port for POP (default 110).

Syntax

property MailPort: Integer read get_MailPort write set_MailPort;

Default Value

110

Remarks

This property contains the server port for POP (default 110). A valid port number (a value between 1 and 65535) is required for the connection to take place. The property must be set before a connection is attempted and cannot be changed once a connection is established. Any attempt to change this property while connected will fail with an error.

For implicit Secure Sockets Layer (SSL), use port 995 (please refer to the SSLStartMode property for more information).

This property is not available at design time.

MailServer Property (PPOP Component)

This property includes the name or address of a mail server (internet post office server).

Syntax

property MailServer: String read get_MailServer write set_MailServer;

Default Value

''

Remarks

This property specifies the IP address (IP number in dotted internet format) or the domain name of the mail server. It is set before a connection is attempted and cannot be changed once a connection is in progress.

If this property is set to a domain name, a DNS request is initiated. Upon successful termination of the request, this property is set to the corresponding address. If the search is not successful, the component raises an exception.

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

MaxLines Property (PPOP Component)

This property includes the maximum number of message lines other than headers to retrieve.

Syntax

property MaxLines: Integer read get_MaxLines write set_MaxLines;

Default Value

0

Remarks

This property is used to limit the number of text lines other than headers retrieved for messages. It can be used to preview message headers and a portion of their contents, without incurring the overhead of downloading the entire message.

The default value of the property is 0. In this case, the entire message will be retrieved, without interruptions. Note: If you are not retrieving the entire message (MaxLines is nonzero), no data will be written to LocalFile.

Message Property (PPOP Component)

This property provides the raw message content.

Syntax

property Message: String read get_Message;
property MessageB: TBytes read get_MessageB;

Default Value

''

Remarks

This property is populated after calling Retrieve and holds the raw message content. This can be used to access the data before any processing is done by the component.

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

MessageCc Property (PPOP Component)

This property includes the value of the CC header of the last retrieved message.

Syntax

property MessageCc: String read get_MessageCc;

Default Value

''

Remarks

This property contains the value of the CC header of the last retrieved message. The same information also may be retrieved through the Header event.

This property is read-only.

MessageCount Property (PPOP Component)

This property includes the number of messages in the mailbox.

Syntax

property MessageCount: Integer read get_MessageCount;

Default Value

0

Remarks

This property contains the number of messages in the mailbox. When the component is not connected to the server, the value of this property is 0. When connected, it contains the number of messages in the mailbox as reported by the POP server.

This property is read-only.

MessageDate Property (PPOP Component)

This property includes the value of the date header of the last retrieved message.

Syntax

property MessageDate: String read get_MessageDate;

Default Value

''

Remarks

This property contains the value of the date header of the last retrieved message. The same information also may be retrieved through the Header event.

This property is read-only.

MessageFrom Property (PPOP Component)

This property includes the value of the from header of the last retrieved message.

Syntax

property MessageFrom: String read get_MessageFrom;

Default Value

''

Remarks

This property contains the value of the from header of the last retrieved message. The same information also may be retrieved through the Header event.

This property is read-only.

MessageHeaders Property (PPOP Component)

This property includes a collection of the message headers as retrieved from the server.

Syntax

property MessageHeaders: TipgHeaderList read get_MessageHeaders;

Remarks

This property contains a collection of the message headers as retrieved from the server. If the component is not connected, or MessageNumber does not contain a valid message number, the value of this property is an empty collection. Otherwise, it contains a parsed collection of the full headers of the mail message as reported by the server.

The MailServer is asked about the headers of the message only if the MessageNumber property has changed. If MessageNumber has not changed, the component returns a cached value.

Example. Connect and Retrieve Messages:

POPControl.MailServer = "MyPOPServer" POPControl.User = "username" POPControl.Password = "password" POPControl.Connect() POPControl.MessageNumber = 1 MessageText = POPControl.MessageText MessageHeaders = POPControl.MessageHeaders

This property is read-only.

MessageHeadersString Property (PPOP Component)

This property includes a string representation of the full headers of the message as retrieved from the server.

Syntax

property MessageHeadersString: String read get_MessageHeadersString;

Default Value

''

Remarks

This property contains a string representation of the full headers of the message as retrieved from the server. If the component is not connected, or MessageNumber does not contain a valid message number, the value of this property is an empty string. Otherwise, it contains the full headers of the mail message as reported by the server.

The MailServer is asked about the headers of the message only if the MessageNumber property has changed. If MessageNumber has not changed, the component returns a cached value.

Example. Connect and Retrieve Messages:

POPControl.MailServer = "MyPOPServer" POPControl.User = "username" POPControl.Password = "password" POPControl.Connect() POPControl.MessageNumber = 1 MessageText = POPControl.MessageText MessageHeadersString = POPControl.MessageHeadersString

This property is read-only.

MessageNumber Property (PPOP Component)

This property includes the current (selected) message.

Syntax

property MessageNumber: Integer read get_MessageNumber write set_MessageNumber;

Default Value

1

Remarks

This property indicates the current (selected) message. This property specifies a message number in between 1 and MessageCount. The various component methods related to single messages use this property as a message pointer (see method descriptions and the QueryMessageSize method).

MessageRecipients Property (PPOP Component)

This property includes a collection of recipients for the current message.

Syntax

property MessageRecipients: TipgMessageRecipientList read get_MessageRecipients;

Remarks

This property contains a collection of recipients for the current message. This collection describes all of the people to whom the last retrieved message was sent. Each MessageRecipient contains information describing that recipient, and what type of recipient it is.

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

MessageReplyTo Property (PPOP Component)

This property includes the value of the Reply-To header of the last retrieved message.

Syntax

property MessageReplyTo: String read get_MessageReplyTo;

Default Value

''

Remarks

This property contains the value of the Reply-To header of the last retrieved message. The same information also may be retrieved through the Header event.

This property is read-only.

MessageSubject Property (PPOP Component)

This property includes the value of the Subject header of the last retrieved message.

Syntax

property MessageSubject: String read get_MessageSubject;

Default Value

''

Remarks

This property contains the value of the Subject header of the last retrieved message. The same information also may be retrieved through the Header event.

This property is read-only.

MessageText Property (PPOP Component)

This property includes the full text of the message as retrieved from the server.

Syntax

property MessageText: String read get_MessageText;

Default Value

''

Remarks

This property contains the full text of the message as retrieved from the server. If the component is not connected, or MessageNumber does not contain a valid message number, the value of this property is an empty string. Otherwise, it contains the text of the mail message as reported by the server (a maximum of MaxLines).

The MailServer is asked about the text of the message only if the MessageNumber property has changed. If MessageNumber has not changed, the component returns a cached value.

Example. Connect and Retrieve Messages:

POPControl.MailServer = "MyPOPServer" POPControl.User = "username" POPControl.Password = "password" POPControl.Connect() POPControl.MessageNumber = 1 MessageText = POPControl.MessageText MessageHeaders = POPControl.MessageHeaders

This property is read-only.

MessageTo Property (PPOP Component)

This property includes the value of the To header of the last retrieved message.

Syntax

property MessageTo: String read get_MessageTo;

Default Value

''

Remarks

This property contains the value of the To header of the last retrieved message. The same information also may be retrieved through the Header event.

This property is read-only.

Password Property (PPOP Component)

This property includes the password for the mailbox user.

Syntax

property Password: String read get_Password write set_Password;

Default Value

''

Remarks

This property contains the password for the mailbox user. This property must be set before the component connects to the MailServer.

SignerKeys Property (PPOP Component)

The collection of keys belonging to the signer of the message.

Syntax

property SignerKeys: TipgKeyList read get_SignerKeys write set_SignerKeys;

Remarks

This property contains the keys of the message signer.

Set this property before calling VerifySignature or DecryptAndVerifySignature.

This property is not available at design time.

SSLAcceptServerCert Property (PPOP Component)

Instructs the component to unconditionally accept the server certificate that matches the supplied certificate.

Syntax

property SSLAcceptServerCert: TipgCertificate read get_SSLAcceptServerCert write set_SSLAcceptServerCert;

Remarks

If it finds any issues with the certificate presented by the server, the component will normally terminate the connection with an error.

You may override this behavior by supplying a value for SSLAcceptServerCert. If the certificate supplied in SSLAcceptServerCert is the same as the certificate presented by the server, then the server certificate is accepted unconditionally, and the connection will continue normally.

Note: This functionality is provided only for cases in which you otherwise know that you are communicating with the right server. If used improperly, this property may create a security breach. Use it at your own risk.

SSLCert Property (PPOP Component)

The certificate to be used during Secure Sockets Layer (SSL) negotiation.

Syntax

property SSLCert: TipgCertificate read get_SSLCert write set_SSLCert;

Remarks

This property includes the digital certificate that the component will use during SSL negotiation. Set this property to a valid certificate before starting SSL negotiation. To set a certificate, you may set the Encoded field to the encoded certificate. To select a certificate, use the store and subject fields.

SSLEnabled Property (PPOP Component)

This property indicates whether Transport Layer Security/Secure Sockets Layer (TLS/SSL) is enabled.

Syntax

property SSLEnabled: Boolean read get_SSLEnabled write set_SSLEnabled;

Default Value

false

Remarks

This property specifies whether TLS/SSL is enabled in the component. When False (default), the component operates in plaintext mode. When True, TLS/SSL is enabled.

TLS/SSL may also be enabled by setting SSLStartMode. Setting SSLStartMode will automatically update this property value.

This property is not available at design time.

SSLProvider Property (PPOP Component)

The Secure Sockets Layer/Transport Layer Security (SSL/TLS) implementation to use.

Syntax

property SSLProvider: TipgTSSLProviders read get_SSLProvider write set_SSLProvider;

TipgTSSLProviders = (
  sslpAutomatic,
  sslpPlatform,
  sslpInternal
);

Default Value

sslpAutomatic

Remarks

This property specifies the SSL/TLS implementation to use. In most cases the default value of 0 (Automatic) is recommended and should not be changed. When set to 0 (Automatic), the component will select whether to use the platform implementation or the internal implementation depending on the operating system as well as the TLS version being used.

Possible values are as follows:

In most cases using the default value (Automatic) is recommended. The component will select a provider depending on the current platform.

When Automatic is selected, on Windows, the component will use the platform implementation. On Linux/macOS, the component will use the internal implementation. When TLS 1.3 is enabled via SSLEnabledProtocols, the internal implementation is used on all platforms.

SSLServerCert Property (PPOP Component)

The server certificate for the last established connection.

Syntax

property SSLServerCert: TipgCertificate read get_SSLServerCert;

Remarks

This property contains the server certificate for the last established connection.

SSLServerCert is reset every time a new connection is attempted.

This property is read-only.

SSLStartMode Property (PPOP Component)

This property determines how the component starts the Secure Sockets Layer (SSL) negotiation.

Syntax

property SSLStartMode: TipgTSSLStartModes read get_SSLStartMode write set_SSLStartMode;

TipgTSSLStartModes = (
  sslAutomatic,
  sslImplicit,
  sslExplicit,
  sslNone
);

Default Value

sslNone

Remarks

The SSLStartMode property may have one of the following values:

Timeout Property (PPOP Component)

The timeout for the component.

Syntax

property Timeout: Integer read get_Timeout write set_Timeout;

Default Value

60

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 component will wait for the operation to complete before returning control.

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

If Timeout expires, and the operation is not yet complete, the component raises an exception.

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

The default value for the Timeout property is 60 seconds.

User Property (PPOP Component)

This property includes the user identifier for the mailbox.

Syntax

property User: String read get_User write set_User;

Default Value

''

Remarks

This property contains the user identifier for the mailbox. This property must be set before the component connects to the MailServer.

Config Method (PPOP Component)

Sets or retrieves a configuration setting.

Syntax

function Config(ConfigurationString: String): String;

Remarks

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

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

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

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

Connect Method (PPOP Component)

This method connects to the mail server and attempts to log in.

Syntax

procedure Connect();

Remarks

This method connects to the mail server and attempts to log in using the current User and Password. Then it retrieves the initial statistics about the mailbox contents (MessageCount and QueryTotalSize).

Example. Connect to POP Mailbox:

POPControl.MailServer = "MyPOPServer" POPControl.User = "username" POPControl.Password = "password" POPControl.Connect() POPControl.MessageNumber = 1 POPControl.Retrieve() MessageText = POPControl.MessageText MessageHeaders = POPControl.MessageHeaders

Decrypt Method (PPOP Component)

Decrypts the message.

Syntax

procedure Decrypt();

Remarks

This method decrypts the specified message.

The message will be decrypted using the keys specified in Keys. Before decryption begins the component will fire the RecipientInfo event with information about the encrypted message, including the key used to encrypt the message. Within this event you may use the available information to load the correct key into Keys.

DecryptAndVerifySignature Method (PPOP Component)

Decrypts and verifies the signature of the message.

Syntax

procedure DecryptAndVerifySignature();

Remarks

This method attempts to both decrypt and verify the signature of the message. All of the properties affected by calling the Decrypt and VerifySignature methods are affected in the same manner.

This method may be used when the data is signed, encrypted, or signed and encrypted. For instance, if the data is encrypted but not signed you may still use this method and the component will perform the decryption without error.

The message will be decrypted using the keys specified in Keys. Before decryption begins the component will fire the RecipientInfo event with information about the encrypted message, including the key used to encrypt the message. Within this event you may use the available information to load the correct key into Keys.

The message will be verified using the keys specified in SignerKeys. Before verification begins the component will fire the SignatureInfo event with information about the signature including the key used to sign the message. Within this event you may use the information available to load the correct key into SignerKeys.

By default, if the signature is not valid the component raises an exception. The configuration setting RequireValidSignature may be set to False to disable this requirement. When RequireValidSignature is set to False, the Status parameter of the VerificationStatus event should be checked to determine the result of the operation.

NOTE: This method does not attempt to check the validity of the signing key itself.

Delete Method (PPOP Component)

This method deletes a message specified by MessageNumber on the server.

Syntax

procedure Delete();

Remarks

This method asks the MailServer to delete the message specified by MessageNumber. The message will not actually be deleted from the server until the connection is closed. To cancel a previous Delete, use the Reset method.

Disconnect Method (PPOP Component)

This method disconnects from the mail server.

Syntax

procedure Disconnect();

Remarks

This method makes the component disconnect from the MailServer by sending the QUIT command. If successful, all changes to the mailbox are committed by the server. Otherwise, changes are rolled back to the initial state that the server was in before the connection.

DoEvents Method (PPOP Component)

This method processes events from the internal message queue.

Syntax

procedure DoEvents();

Remarks

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

Interrupt Method (PPOP Component)

This method interrupts the current method.

Syntax

procedure Interrupt();

Remarks

If there is no method in progress, Interrupt simply returns, doing nothing.

ListMessageSizes Method (PPOP Component)

This method retrieves a list of all message sizes from the server.

Syntax

procedure ListMessageSizes();

Remarks

This message retrieves a list of all message sizes from the server. For each message listed, a MessageList event will fire containing the number and size of the message.

ListMessageUIDs Method (PPOP Component)

This method retrieves a list of all message UIDs from the server.

Syntax

procedure ListMessageUIDs();

Remarks

This method retrieves a list of all message UIDs from the server. For each message listed, a MessageList event will fire containing the number and UID of the message.

LocalizeDate Method (PPOP Component)

This method converts a valid RFC 822 message date to a local date and time.

Syntax

function LocalizeDate(DateTime: String): String;

Remarks

This method can be used to convert an RFC 822 date and time string to the corresponding local date and time.

Note: Dates will be returned in the format: "MM/dd/yyyy hh:mm:ss".

QueryMessageSize Method (PPOP Component)

This method returns the size in bytes of the current message.

Syntax

function QueryMessageSize(): Int64;

Remarks

This method queries the server for the size in bytes of the message specified by MessageNumber. The method returns the size (in bytes) of the message.

If the component is not connected, or MessageNumber does not contain a valid message number, the return value is 0. Otherwise, it returns the size of the mail message (including headers) as reported by the server.

The MailServer is asked about the size of the message only if the MessageNumber property has changed. If MessageNumber has not changed, the component returns a cached value.

QueryMessageUID Method (PPOP Component)

This method returns the unique identifier (UID) of the message as specified by the server.

Syntax

function QueryMessageUID(): String;

Remarks

This method returns the unique identifier (UID) of the message specified by MessageNumber. If the component is not connected, or MessageNumber does not contain a valid message number, the return value of this method is an empty string. Otherwise, it returns the UID of the mail message as reported by the server.

The MailServer is asked about the UID of the message only if the MessageNumber property has changed. If MessageNumber has not changed, the component returns a cached value.

QueryTotalSize Method (PPOP Component)

This method returns the cumulative size in bytes of messages in the mailbox (including headers).

Syntax

function QueryTotalSize(): Int64;

Remarks

This method returns the cumulative size in bytes of messages in the mailbox (including headers). When the component is not connected to the server, the return value of this method is 0. When connected, it returns the cumulative size of all the messages in the mail box as reported by the POP server.

Reset Method (PPOP Component)

This method resets all changes and revert back to the state when the user first connected.

Syntax

procedure Reset();

Remarks

This method is used to reset all changes and revert back to the state when the user first connected. Asks the MailServer to reset all changes and revert back to the state it was when connected.

Retrieve Method (PPOP Component)

This method retrieves a message specified by MessageNumber from the server.

Syntax

procedure Retrieve();

Remarks

This method is used to retrieve a message specified by MessageNumber from the server. It asks the MailServer to retrieve the message specified by MessageNumber. The message headers will arrive in the Header event, and the message text will arrive in the Transfer event.

The MaxLines property defines the number of lines retrieved.

Example. Connect and Retrieve Messages:

POPControl.MailServer = "MyPOPServer" POPControl.User = "username" POPControl.Password = "password" POPControl.Connect() POPControl.MessageNumber = 1 POPControl.Retrieve()

RetrieveHeaders Method (PPOP Component)

This method retrieves headers for a message specified by MessageNumber .

Syntax

procedure RetrieveHeaders();

Remarks

Calling this method will retrieve the headers for the message specified by the MessageNumber property. The message headers will be provided by the Header event and also stored in the MessageHeaders property.

Example. Connect and Retrieve Message Headers:

POPControl.MailServer = "MyPOPServer" POPControl.User = "username" POPControl.Password = "password" POPControl.Connect() POPControl.MessageNumber = 1 POPControl.RetrieveHeaders()

SendCommand Method (PPOP Component)

This method sends the exact command directly to the server.

Syntax

procedure SendCommand(Command: String);

Remarks

This method sends the command specified by Command to the server exactly as it is provided. Use this method to send additional or custom commands directly to the server.

After calling this method, check the LastReply property or monitor the PITrail event to obtain the server's response.

SetMessageStream Method (PPOP Component)

This method sets the stream to which the message downloaded from the server will be written.

Syntax

procedure SetMessageStream(MessageStream: TStream);

Remarks

This method sets the stream to which the message downloaded from the server will be written. If a download stream is set before the Retrieve method is called, the downloaded data will be written to the stream. The stream should be open and normally set to position 0. The component will automatically close this stream if CloseStreamAfterTransfer is set to True (default). If the stream is closed, you will need to call SetMessageStream again before calling Retrieve again. The downloaded content will be written starting at the current position in the stream.

Note: SetMessageStream and LocalFile will reset the other.

VerifySignature Method (PPOP Component)

Verifies the signature of the current message.

Syntax

procedure VerifySignature();

Remarks

This method verifies the signature of the message.

The message will be verified using the keys specified in SignerKeys. Before verification begins the component will fire the SignatureInfo event with information about the signature including the key used to sign the message. Within this event you may use the information available to load the correct key into SignerKeys.

By default, if the signature is not valid the component raises an exception. The configuration setting RequireValidSignature may be set to False to disable this requirement. When RequireValidSignature is set to False, the Status parameter of the VerificationStatus event should be checked to determine the result of the operation.

ConnectionStatus Event (PPOP Component)

Fired to indicate changes in the connection state.

Syntax

type TConnectionStatusEvent = procedure (
  Sender: TObject;
  const ConnectionEvent: String;
  StatusCode: Integer;
  const Description: String
) of Object;

property OnConnectionStatus: TConnectionStatusEvent read FOnConnectionStatus write FOnConnectionStatus;

Remarks

This event is fired when the connection state changes: for example, completion of a firewall or proxy connection or completion of a security handshake.

The ConnectionEvent parameter indicates the type of connection event. Values may include the following:

EndTransfer Event (PPOP Component)

This event is fired when the message completes transferring.

Syntax

type TEndTransferEvent = procedure (
  Sender: TObject;
  Direction: Integer
) of Object;

property OnEndTransfer: TEndTransferEvent read FOnEndTransfer write FOnEndTransfer;

Remarks

The EndTransfer event is fired when the message body completes transferring from the server to the local host.

The Direction parameter shows whether the client (0) or the server (1) is sending the data.

Error Event (PPOP Component)

Fired when information is available about errors during data delivery.

Syntax

type TErrorEvent = procedure (
  Sender: TObject;
  ErrorCode: Integer;
  const Description: String
) of Object;

property OnError: TErrorEvent read FOnError write FOnError;

Remarks

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

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

Header Event (PPOP Component)

This event is fired for every message header being retrieved.

Syntax

type THeaderEvent = procedure (
  Sender: TObject;
  const Field: String;
  const Value: String
) of Object;

property OnHeader: THeaderEvent read FOnHeader write FOnHeader;

Remarks

The Field parameter contains the name of the header (in the same case as it is delivered). The Value parameter contains the header contents.

If the header line being retrieved is a continuation header line, then the Field parameter contains '' (empty string).

KeyPassphrase Event (PPOP Component)

Fired if the passphrase of current key is incorrect or empty.

Syntax

type TKeyPassphraseEvent = procedure (
  Sender: TObject;
  const UserId: String;
  const KeyId: String;
  const Fingerprint: String;
  var Passphrase: String
) of Object;

property OnKeyPassphrase: TKeyPassphraseEvent read FOnKeyPassphrase write FOnKeyPassphrase;

Remarks

This event fires when the passphrase for the key is required. The passphrase must be specified before operations requiring the secret key are attempted. The passphrase may be supplied by setting the Passphrase parameter in this event, or by specifying the Passphrase property before attempting the operation.

The passphrase is required when using the following methods in KeyMgr:

• AddUserId
• SignUserId
• ChangeExpirationDate
• ChangePassphrase

When using the OpenPGP component, or an email-based component, the following methods require a passphrase for the key:

• Decrypt
• Sign
• SignAndEncrypt

UserId holds the user Id of the key the passphrase is required for.

The UserId format is:

FirstName LastName (Comment) <Email>

Note that for OpenPGP v6, a key may be created with or without a UserId, as the field is optional. If a key was created without a UserId, the key's Fingerprint can be used as it's identifier instead.

KeyId is the hex-encoded, 4-byte or 8-byte Id of the key the passphrase is required for. For OpenPGP v4 keys and earlier, the key Id corresponds to the last 4 or 8 bytes of the key's Fingerprint. For OpenPGP v6 keys, the key Id corresponds to the first 8 bytes of the key's Fingerprint instead. For instance:

5E70662EA810E768

Fingerprint holds the hex-encoded, 20-byte fingerprint of the key the passphrase is required for. This is in the form:

5E70662EA810E768391A2FE8F7B7D49C89C9D7B1

MessageList Event (PPOP Component)

This event is fired for every message listed by ListMessageSizes and/or ListMessageUIDs .

Syntax

type TMessageListEvent = procedure (
  Sender: TObject;
  MessageNumber: Integer;
  const MessageUID: String;
  MessageSize: Integer
) of Object;

property OnMessageList: TMessageListEvent read FOnMessageList write FOnMessageList;

Remarks

When ListMessageSizes is called, MessageSize is valid, and MessageUID is always an empty string.

When ListMessageUIDs is called, MessageUID is valid, and MessageSize is 0.

PITrail Event (PPOP Component)

This event traces the commands sent to the mail server, and the respective replies.

Syntax

type TPITrailEvent = procedure (
  Sender: TObject;
  Direction: Integer;
  const Message: String
) of Object;

property OnPITrail: TPITrailEvent read FOnPITrail write FOnPITrail;

Remarks

The PITrail event is useful for debugging purposes. It shows all of the interaction between the client and the server, line by line, except for message header and body transfers.

The Message parameter contains the full text of the message. The Direction parameter shows the originator of the message:

Progress Event (PPOP Component)

Fired as progress is made.

Syntax

type TProgressEvent = procedure (
  Sender: TObject;
  BytesProcessed: Int64;
  PercentProcessed: Integer
) of Object;

property OnProgress: TProgressEvent read FOnProgress write FOnProgress;

Remarks

This event is fired automatically as data is processed by the component.

The PercentProcessed parameter indicates the current status of the operation.

The BytesProcessed parameter holds the total number of bytes processed so far.

RecipientInfo Event (PPOP Component)

Fired for each recipient key of the encrypted message.

Syntax

type TRecipientInfoEvent = procedure (
  Sender: TObject;
  const KeyId: String;
  const Fingerprint: String;
  const PublicKeyAlgorithm: String
) of Object;

property OnRecipientInfo: TRecipientInfoEvent read FOnRecipientInfo write FOnRecipientInfo;

Remarks

This event fires when the Decrypt or DecryptAndVerifySignature method is called.

KeyId is the hex-encoded 4- or 8-byte Id of the key used to encrypt the message. If a subkey was used to encrypt the message this will be the Id of that subkey. For OpenPGP v4 keys and earlier, the key Id corresponds to the last 4 or 8 bytes of the key's Fingerprint. For OpenPGP v6 keys, the key Id corresponds to the first 8 bytes of the key's Fingerprint instead. For instance:

5E70662EA810E768

Fingerprint holds the hex-encoded, 20-byte fingerprint of the key. This is in the form:

5E70662EA810E768391A2FE8F7B7D49C89C9D7B1

The KeyId and Fingerprint parameters can be used to identify the correct key to specify in Keys. Keys can be set from within this event as this event fires directly before the decryption process begins.

It is recommended to use the Fingerprint to identify the correct key, as it is possible for different keys to have the same KeyId.

PublicKeyAlgorithm is the algorithm of the public key used to encrypt the message. Possible values are:

• RSA
• DSA
• ECDSA
• EdDSA
• Ed25519
• Ed448
• RSA-Legacy
• ECDH (Subkeys only)
• X25519 (Subkeys only)
• X448 (Subkeys only)

SignatureInfo Event (PPOP Component)

Fired during verification of the signed message.

Syntax

type TSignatureInfoEvent = procedure (
  Sender: TObject;
  const KeyId: String;
  const Fingerprint: String;
  const SigningAlgorithm: String;
  const PublicKeyAlgorithm: String
) of Object;

property OnSignatureInfo: TSignatureInfoEvent read FOnSignatureInfo write FOnSignatureInfo;

Remarks

This event fires when the VerifySignature or DecryptAndVerifySignature method is called. It provides information about the signature of the message.

KeyId is the hex-encoded 4- or 8-byte Id of the key used to sign the message. If a subkey was used to sign the message this will be the Id of that subkey. For OpenPGP v4 keys and earlier, the key Id corresponds to the last 4 or 8 bytes of the key's Fingerprint. For OpenPGP v6 keys, the key Id corresponds to the first 8 bytes of the key's Fingerprint instead. For instance:

5E70662EA810E768

Fingerprint holds the hex-encoded, 20-byte fingerprint of the key. This is in the form:

5E70662EA810E768391A2FE8F7B7D49C89C9D7B1

The KeyId and Fingerprint parameters can be used to identify the correct key to specify in SignerKeys. SignerKeys can be set from within this event as this event fires directly before the verification process begins.

It is recommended to use the Fingerprint to identify the correct key, as it is possible for different keys to have the same KeyId.

SigningAlgorithm describes the hash algorithm used when the message was originally signed. This value is applicable only to the message signature, not the key used to sign the message. Possible values are:

• SHA1
• MD5
• SHA256
• SHA384
• SHA512
• SHA224
• RIPEMD160
• SHA3-256
• SHA3-512

PublicKeyAlgorithm is the algorithm of the public key used to sign the message. Possible values are:

• RSA
• DSA
• ECDSA
• EdDSA
• Ed25519
• Ed448
• RSA-Legacy
• ECDH (Subkeys only)
• X25519 (Subkeys only)
• X448 (Subkeys only)

SSLServerAuthentication Event (PPOP Component)

Fired after the server presents its certificate to the client.

Syntax

type TSSLServerAuthenticationEvent = procedure (
  Sender: TObject;
  const CertEncoded: String;
  const CertEncodedB: TBytes;
  const CertSubject: String;
  const CertIssuer: String;
  const Status: String;
  var Accept: Boolean
) of Object;

property OnSSLServerAuthentication: TSSLServerAuthenticationEvent read FOnSSLServerAuthentication write FOnSSLServerAuthentication;

Remarks

During this event, the client can decide whether or not to continue with the connection process. The Accept parameter is a recommendation on whether to continue or close the connection. This is just a suggestion: application software must use its own logic to determine whether or not to continue.

When Accept is False, Status shows why the verification failed (otherwise, Status contains the string OK). If it is decided to continue, you can override and accept the certificate by setting the Accept parameter to True.

SSLStatus Event (PPOP Component)

Fired when secure connection progress messages are available.

Syntax

type TSSLStatusEvent = procedure (
  Sender: TObject;
  const Message: String
) of Object;

property OnSSLStatus: TSSLStatusEvent read FOnSSLStatus write FOnSSLStatus;

Remarks

The event is fired for informational and logging purposes only. This event tracks the progress of the connection.

StartTransfer Event (PPOP Component)

This event is fired when the message starts transferring.

Syntax

type TStartTransferEvent = procedure (
  Sender: TObject;
  Direction: Integer
) of Object;

property OnStartTransfer: TStartTransferEvent read FOnStartTransfer write FOnStartTransfer;

Remarks

The StartTransfer event is fired when the message body starts transferring from the server to the local host.

The Direction parameter shows whether the client (0) or the server (1) is sending the data.

Status Event (PPOP Component)

Shows the progress of the operation.

Syntax

type TStatusEvent = procedure (
  Sender: TObject;
  const Message: String
) of Object;

property OnStatus: TStatusEvent read FOnStatus write FOnStatus;

Remarks

The event is fired for informational and logging purposes only. It may be used to track the progress of an operation.

The level of detail is controlled by the LogLevel setting.

Transfer Event (PPOP Component)

This event is fired when the message is transferred from MailServer .

Syntax

type TTransferEvent = procedure (
  Sender: TObject;
  Direction: Integer;
  BytesTransferred: Int64;
  PercentDone: Integer;
  const Text: String;
  const TextB: TBytes;
  EOL: Boolean
) of Object;

property OnTransfer: TTransferEvent read FOnTransfer write FOnTransfer;

Remarks

The Text parameter contains the portion of the message data to be retrieved.

The BytesTransferred parameter contains the number of bytes transferred since the beginning of the message, including header bytes. At the end of transmission (i.e., when the last Transfer event is fired), BytesTransferred equals the value of the QueryMessageSize method.

The Transfer event is fired for every line of the message. For complete lines, there is no terminating newline at the end of the Text parameter, and EOL is True. The EOL parameter is False when a line is broken (usually for being too long).

A faster way to retrieve a message is to assign a value to the LocalFile property and use the Transfer event to check the progress rather than to get the actual data.

The Direction parameter shows whether the client (0) or the server (1) is sending the data.

The PercentDone parameter shows the progress of the transfer in the corresponding direction. If PercentDone can not be calculated the value will be -1.

Note: Events are not re-entrant. Performing time-consuming operations within this event will prevent it from firing again in a timely manner and may affect overall performance.

Note: For the PercentDone parameter value to be correct, the GetMessageSize configuration setting must be set to True.

VerificationStatus Event (PPOP Component)

Fired after verification of the signed message.

Syntax

type TVerificationStatusEvent = procedure (
  Sender: TObject;
  const KeyId: String;
  const Fingerprint: String;
  Status: Integer
) of Object;

property OnVerificationStatus: TVerificationStatusEvent read FOnVerificationStatus write FOnVerificationStatus;

Remarks

This event fires when VerifySignature or DecryptAndVerifySignature is called. It provides information about the result.

KeyId is the hex-encoded 4- or 8-byte Id of the key used to sign the message. For OpenPGP v4 keys and earlier, the key Id corresponds to the last 4 or 8 bytes of the key's Fingerprint. For OpenPGP v6 keys, the key Id corresponds to the first 8 bytes of the key's Fingerprint instead. For instance:

5E70662EA810E768

Fingerprint holds the hex-encoded, 20-byte fingerprint of the key. This is in the form:

5E70662EA810E768391A2FE8F7B7D49C89C9D7B1

Status holds the result of the operation. Possible values are:

Certificate Type

This is the digital certificate being used.

Remarks

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

Fields

Constructors

>

constructor Create();

constructor Create(valEncoded: TBytes);

constructor Create(valStoreType: TipgCertStoreTypes; valStore: String; valStorePassword: String; valSubject: String);

constructor Create(valStoreType: TipgCertStoreTypes; valStore: TBytes; valStorePassword: String; valSubject: String);

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

Constructors

constructor Create();

Header Type

This is an HTTP header as it is received from the server.

Remarks

When a header is received through a Header event, it is parsed into a Header type. This type contains a Field, and its corresponding Value.

Fields

Constructors

constructor Create();

constructor Create(valField: String; valValue: String);

Key Type

The OpenPGP key being used.

Remarks

This type describes the current key. The key may be a public or secret key. The fields are used to identify or select the key.

Fields

5E70662EA810E768391A2FE8F7B7D49C89C9D7B1

5E70662EA810E768

FirstName LastName (Comment) <Email>

MessageRecipient Type

This types describes the message recipient.

Remarks

This type describes who the message is sent to. It includes fields to denote the name and email address of the recipient of the message. The type of recipient must also be specified if the component is sending the message.

Fields

Constructors

constructor Create();

constructor Create(valAddress: String);

Config Settings (PPOP Component)

PPOP Config Settings

POP Config Settings

TCPClient Config Settings

SSL Config Settings

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
... Intermediate Cert ...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
... Root Cert ...
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
... Intermediate Cert ...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
... Root Cert ...
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

-----BEGIN CERTIFICATE-----
MIIEKzCCAxOgAwIBAgIRANTET4LIkxdH6P+CFIiHvTowDQYJKoZIhvcNAQELBQAw
... Intermediate Cert...
eWHV5OW1K53o/atv59sOiW5K3crjFhsBOd5Q+cJJnU+SWinPKtANXMht+EDvYY2w
F0I1XhM+pKj7FjDr+XNj
-----END CERTIFICATE-----
\r \n
-----BEGIN CERTIFICATE-----
MIIEFjCCAv6gAwIBAgIQetu1SMxpnENAnnOz1P+PtTANBgkqhkiG9w0BAQUFADBp
... Root Cert...
d8q23djXZbVYiIfE9ebr4g3152BlVCHZ2GyPdjhIuLeH21VbT/dyEHHA
-----END CERTIFICATE-----

Socket Config Settings

Base Config Settings

Trappable Errors (PPOP Component)

POP Errors

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

TCPClient Errors

SSL Errors

TCP/IP Errors

OpenPGP Errors