IPWorks OpenPGP 2020 macOS Edition

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PPOP Module

Properties   Methods   Events   Configuration Settings   Errors  

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




The PPOP class 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 class 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).


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.


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 module with short descriptions. Click on the links for further details.

AuthMechanismThe authentication mechanism to be used when connecting to the mail server.
CommandUsed to send additional commands directly to the server.
ConnectedShows whether the component is connected.
FirewallA set of properties related to firewall access.
IdleThe current status of the component.
IncludeHeadersInstructs the component to include the headers in the MessageText and LocalFile.
KeysA collection of keys used for cryptographic operations.
LastReplyThe last reply from the server.
LocalHostThe name of the local host or user-assigned IP interface through which connections are initiated or accepted.
MailPortThe server port for POP (default 110).
MailServerThe name or address of a mail server (internet post office server).
MaxLinesThe maximum number of message lines besides headers to retrieve.
MessageProvides the raw message content.
MessageCcThe value of the CC header of the last retrieved message.
MessageCountThe number of messages in the mailbox.
MessageDateThe value of the date header of the last retrieved message.
MessageFromThe value of the from header of the last retrieved message.
MessageHeadersCollection of the message headers as retrieved from the server.
MessageHeadersStringA string representation of the full headers of the message as retrieved from the server.
MessageNumberCurrent (selected) message.
MessageRecipientsA collection of recipients for the current message.
MessageReplyToThe value of the Reply-To header of the last retrieved message.
MessageSizeThe size in bytes of the current message.
MessageSubjectThe value of the Subject header of the last retrieved message.
MessageTextThe full text of the message as retrieved from the server.
MessageToThe value of the To header of the last retrieved message.
MessageUIDThe unique identifier of the message as specified by the server.
PasswordThe password for the mailbox user.
SignerKeysThe collection of keys belonging to the signer of the message.
SSLAcceptServerCertEncodedThe certificate (PEM/base64 encoded).
SSLCertEncodedThe certificate (PEM/base64 encoded).
SSLCertStoreThe name of the certificate store for the client certificate.
SSLCertStorePasswordIf 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.
SSLCertStoreTypeThe type of certificate store for this certificate.
SSLCertSubjectThe subject of the certificate used for client authentication.
SSLEnabledWhether TLS/SSL is enabled.
SSLServerCertEncodedThe certificate (PEM/base64 encoded).
SSLStartModeDetermines how the component starts the SSL negotiation.
TimeoutA timeout for the component.
TotalSizeCumulative size in bytes of messages in the mailbox (including headers).
UserThe user identifier for the mailbox.

Method List

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

ConfigSets or retrieves a configuration setting.
ConnectConnects to the mail server and attempts to login.
DecryptDecrypts the message.
DecryptAndVerifySignatureDecrypts and verifies the signature of the message.
DeleteDeletes a message specified by MessageNumber on the server.
DisconnectDisconnects from the mail server.
DoEventsProcesses events from the internal message queue.
InterruptInterrupt the current method.
ListMessageSizesRetrieves a list of all message sizes from the server.
ListMessageUIDsRetrieves a list of all message UIDs from the server.
LocalizeDateConverts a valid RFC 822 message date to local date and time.
ResetResets all changes and revert back to the state when the user first connected.
RetrieveRetrieves a message specified by MessageNumber from the server.
RetrieveHeadersRetrieves headers for a message specified by MessageNumber .
VerifySignatureVerifies the signature of the current message.

Event List

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

ConnectionStatusFired to indicate changes in connection state.
EndTransferFired when the message completes transferring.
ErrorInformation about errors during data delivery.
HeaderFired for every message header being retrieved.
KeyPassphraseFired if the passphrase of current key is incorrect or empty.
MessageListFired for every message listed by ListMessageSizes and/or ListMessageUIDs .
PITrailTraces the commands sent to the mail server, and the respective replies.
ProgressFired as progress is made.
RecipientInfoFired for each recipient key of the encrypted message.
SignatureInfoFired during verification of the signed message.
SSLServerAuthenticationFired after the server presents its certificate to the client.
SSLStatusShows the progress of the secure connection.
StartTransferFired when the message starts transferring.
StatusShows the progress of the operation.
TransferFired while the message gets transferred from MailServer .
VerificationStatusFired after verification of the signed message.

Configuration Settings

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

CommentThe OpenPGP message comment.
LogLevelSpecifies the level of detail that is logged.
ProcessAttachmentsWhether or not to process attachments.
RequireValidSignatureSpecifies if an invalid signature is considered an error condition.
SymmetricPassphraseThe password used for symmetric encryption or decryption.
VersionHeaderThe Version header value in the ASCII armored OpenPGP message.
AuthorizationIdentityThe value to use as the authorization identity when SASL authentication is used.
AutoDecodeSubjectInstructs the component to automatically decode message subjects.
GetMessageSizeWhether to poll the server for the message size prior to retrieving it.
MaxLineLengthThe maximum expected length for message lines.
ConnectionTimeoutSets a separate timeout value for establishing a connection.
FirewallAutoDetectTells the component whether or not to automatically detect and use firewall system settings, if available.
FirewallHostName or IP address of firewall (optional).
FirewallPasswordPassword to be used if authentication is to be used when connecting through the firewall.
FirewallPortThe TCP port for the FirewallHost;.
FirewallTypeDetermines the type of firewall to connect through.
FirewallUserA user name if authentication is to be used connecting through a firewall.
KeepAliveIntervalThe retry interval, in milliseconds, to be used when a TCP keep-alive packet is sent and no response is received.
KeepAliveTimeThe inactivity time in milliseconds before a TCP keep-alive packet is sent.
LingerWhen set to True, connections are terminated gracefully.
LingerTimeTime in seconds to have the connection linger.
LocalHostThe name of the local host through which connections are initiated or accepted.
LocalPortThe port in the local host where the component binds.
MaxLineLengthThe maximum amount of data to accumulate when no EOL is found.
MaxTransferRateThe transfer rate limit in bytes per second.
ProxyExceptionsListA semicolon separated list of hosts and IPs to bypass when using a proxy.
TCPKeepAliveDetermines whether or not the keep alive socket option is enabled.
TcpNoDelayWhether or not to delay when sending packets.
UseIPv6Whether to use IPv6.
LogSSLPacketsControls whether SSL packets are logged when using the internal security API.
OpenSSLCADirThe path to a directory containing CA certificates.
OpenSSLCAFileName of the file containing the list of CA's trusted by your application.
OpenSSLCipherListA string that controls the ciphers to be used by SSL.
OpenSSLPrngSeedDataThe data to seed the pseudo random number generator (PRNG).
ReuseSSLSessionDetermines if the SSL session is reused.
SSLCACertsA newline separated list of CA certificate to use during SSL client authentication.
SSLCheckCRLWhether to check the Certificate Revocation List for the server certificate.
SSLCipherStrengthThe minimum cipher strength used for bulk encryption.
SSLEnabledCipherSuitesThe cipher suite to be used in an SSL negotiation.
SSLEnabledProtocolsUsed to enable/disable the supported security protocols.
SSLEnableRenegotiationWhether the renegotiation_info SSL extension is supported.
SSLIncludeCertChainWhether the entire certificate chain is included in the SSLServerAuthentication event.
SSLProviderThe name of the security provider to use.
SSLSecurityFlagsFlags that control certificate verification.
TLS12SignatureAlgorithmsDefines the allowed TLS 1.2 signature algorithms when UseInternalSecurityAPI is True.
TLS12SupportedGroupsThe supported groups for ECC.
TLS13KeyShareGroupsThe groups for which to pregenerate key shares.
TLS13SignatureAlgorithmsThe allowed certificate signature algorithms.
TLS13SupportedGroupsThe supported groups for (EC)DHE key exchange.
AbsoluteTimeoutDetermines whether timeouts are inactivity timeouts or absolute timeouts.
FirewallDataUsed to send extra data to the firewall.
InBufferSizeThe size in bytes of the incoming queue of the socket.
OutBufferSizeThe size in bytes of the outgoing queue of the socket.
BuildInfoInformation about the product's build.
CodePageThe system code page used for Unicode to Multibyte translations.
LicenseInfoInformation about the current license.
UseInternalSecurityAPITells the component whether or not to use the system security libraries or an internal implementation.

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IPWorks OpenPGP 2020 macOS Edition - Version 20.0 [Build 7941]