/* -*- Mode: C -*- $Id$ CRYPTPLUG - an independent cryptography plug-in API Copyright (C) 2001 by Klarälvdalens Datakonsult AB CRYPTPLUG is free software; you can redistribute it and/or modify it under the terms of GNU General Public License as published by the Free Software Foundation; version 2 of the License. CRYPTPLUG is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA */ #ifndef CRYPTPLUG_H #define CRYPTPLUG_H #ifdef __cplusplus extern "C" { #else typedef char bool; #define true 1 #define false 0 #endif //#include //#include //#include /*! \file cryptplug.h \brief Common API header for CRYPTPLUG. CRYPTPLUG is an independent cryptography plug-in API developed for Sphinx-enabeling KMail and Mutt. CRYPTPLUG was designed for the Aegypten project, but it may be used by 3rd party developers as well to design pluggable crypto backends for the above mentioned MUAs. \note All string parameters appearing in this API are to be interpreted as UTF-8 encoded. \see pgpplugin.c \see gpgplugin.c */ /*! \defgroup groupGeneral Loading and Unloading the Plugin, General Functionality The functions in this section are used for loading and unloading plugins. Note that the actual locating of the plugin and the loading and unloading of the dynamic library is not covered here; this is MUA-specific code for which support code might already exist in the programming environments. */ /*! \defgroup groupDisplay Graphical Display Functionality The functions in this section return stationery that the MUAs can use in order to display security functionality graphically. This can be toolbar icons, shortcuts, tooltips, etc. Not all MUAs will use all this functionality. */ /*! \defgroup groupConfig Configuration Support The functions in this section provide the necessary functionality to configure the security functionality as well as to query configuration settings. Since all configuration settings will not be saved with the plugin, but rather with the MUA, there are also functions to set configuration settings programmatically; these will be used on startup of the plugin when the MUA transfers the configuration values it has read into the plugin. Usually, the functions to query and set the configuration values are not needed for anything but saving to and restoring from configuration files. */ /*! \defgroup groupConfigSign Signature Configuration \ingroup groupConfig The functions in this section provide the functionality to configure signature handling and set and query the signature configuration. */ /*! \defgroup groupConfigCrypt Encryption Configuration \ingroup groupConfig The functions in this section provide the functionality to configure encryption handling and set and query the encryption configuration. \note Whenever the term encryption is used here, it is supposed to mean both encryption and decryption, unless otherwise specified. */ /*! \defgroup groupConfigDir Directory Service Configuration \ingroup groupConfig This section contains messages for configuring the directory service. */ /*! \defgroup groupCertHand Certificate Handling The following methods are used to maintain and query certificates. */ /*! \defgroup groupSignAct Signature Actions This section describes methods that are used for working with signatures. */ /*! \defgroup groupCryptAct Encryption and Decryption The following methods are used to encrypt and decrypt email messages. */ /*! \defgroup groupCertAct Certificate Handling Actions The functions in this section provide local certificate management. */ /*! \defgroup groupCRLAct CRL Handling Actions This section describes functions for managing CRLs. */ // dummy values: typedef enum { CryptPlugFeat_undef = 0, CryptPlugFeat_SignMessages = 1, CryptPlugFeat_VerifySignatures = 2, CryptPlugFeat_EncryptMessages = 3, CryptPlugFeat_DecryptMessages = 4 // more to follow ... } Feature; // dummy values typedef enum { PinRequest_undef = 0, PinRequest_Always = 1, PinRequest_OncePerMail = 2, PinRequest_OncePerSession = 3 // may be changed ... } PinRequests; // dummy values: typedef enum { SendCert_undef = 0, SendCert_DontSend = 1, SendCert_SendOwn = 2, SendCert_SendChainWithoutRoot = 3, SendCert_SendChainWithRoot = 4 } SendCertificates; // dummy values: typedef enum { SignAlg_undef = 0, SignAlg_SHA1 = 1 } SignatureAlgorithm; typedef enum { EncryptAlg_undef = 0, EncryptAlg_RSA = 1, EncryptAlg_SHA1 = 2, EncryptAlg_TripleDES = 3 } EncryptionAlgorithm; typedef enum { SignEmail_undef = 0, SignEmail_SignAll = 1, SignEmail_Ask = 2, SignEmail_DontSign = 3 } SignEmail; typedef enum { EncryptEmail_undef = 0, EncryptEmail_EncryptAll = 1, EncryptEmail_Ask = 2, EncryptEmail_DontEncrypt = 3 } EncryptEmail; typedef enum { CertSrc_undef = 0, CertSrc_Server = 1, CertSrc_Local = 2, CertSrc_ServerLocal = CertSrc_Server | CertSrc_Local } CertificateSource; /*! \ingroup groupGeneral \brief This function sets up all internal structures. Plugins that need no initialization should provide an empty implementation. The method returns \c true if the initialization was successful and \c false otherwise. Before this function is called, no other plugin functions should be called; the behavior is undefined in this case. \note This function must be implemented by each plug-in using this API specification. */ bool initialize( void ); /*! \ingroup groupGeneral \brief This function frees all internal structures. Plugins that do not keep any internal structures should provide an empty implementation. After this function has been called, no other plugin functions should be called; the behavior is undefined in this case. \note This function must be implemented by each plug-in using this API specification. */ void deinitialize( void ); /*! \ingroup groupGeneral \brief This function returns \c true if the specified feature is available in the plugin, and \c false otherwise. Not all plugins will support all features; a complete Sphinx implementation will support all features contained in the enum, however. \note This function must be implemented by each plug-in using this API specification. */ bool hasFeature( Feature ); /*! \ingroup groupDisplay \brief Returns stationery to indicate unsafe emails. */ void unsafeStationery( void** pixmap, const char** menutext, char* accel, const char** tooltip, const char** statusbartext ); /*! \ingroup groupDisplay \brief Returns stationery to indicate signed emails. */ void signedStationery( void** pixmap, const char** menutext, char* accel, const char** tooltip, const char** statusbartext ); /*! \ingroup groupDisplay \brief Returns stationery to indicate encrypted emails. */ void encryptedStationery( void** pixmap, const char** menutext, char* accel, const char** tooltip, const char** statusbartext ); /*! \ingroup groupDisplay \brief Returns stationery to indicate signed and encrypted emails. */ void signedEncryptedStationery( void** pixmap, const char** menutext, char* accel, const char** tooltip, const char** statusbartext ); /*! \ingroup groupConfigSign \brief This function returns an XML representation of a configuration dialog for configuring signature handling. The syntax is that of .ui files as specified in the Imhotep documentation. This function does not execute or show the dialog in any way; this is up to the MUA. Also, what the MUA makes of the information provided highly depends on the MUA itself. A GUI-based MUA will probably create a dialog window (possibly integrated into an existing configuration dialog in the application), while a terminal-based MUA might generate a series of questions or a terminal based menu selection. */ const char* signatureConfigurationDialog( void ); /*! \ingroup groupConfigSign \brief This function returns an XML representation of a configuration dialog for selecting a signature key. This will typically be used when the user wants to select a signature key for one specific message only; the defaults are set in the dialog returned by signatureConfigurationDialog(). */ const char* signatureKeySelectionDialog( void ); /*! \ingroup groupConfigSign \brief This function returns an XML representation of a configuration dialog for selecting a signature algorithm. This will typically be used when the user wants to select a signature algorithm for one specific message only; the defaults are set in the dialog returned by signatureConfigurationDialog(). */ const char* signatureAlgorithmDialog( void ); /*! \ingroup groupConfigSign \brief This function returns an XML representation of a configuration dialog for selecting whether an email message and its attachments should be sent with or without signatures. This will typically be used when the user wants to select a signature key for one specific message only; the defaults are set in the dialog returned by signatureConfigurationDialog(). */ const char* signatureHandlingDialog( void ); /*! \ingroup groupConfigSign \brief Sets the signature key certificate that identifies the role of the signer. */ void setSignatureKeyCertificate( const char* certificate ); /*! \ingroup groupConfigSign \brief Returns the signature key certificate that identifies the role of the signer. */ const char* signatureKeyCertificate( void ); /*! \ingroup groupConfigSign \brief Sets the algorithm used for signing. */ void setSignatureAlgorithm( SignatureAlgorithm ); /*! \ingroup groupConfigSign \brief Returns the algorithm used for signing. */ SignatureAlgorithm signatureAlgorithm( void ); /*! \ingroup groupConfigSign \brief Sets which certificates should be sent with the message. */ void setSendCertificates( SendCertificates ); /*! \ingroup groupConfigSign \brief Returns which certificates should be sent with the message. */ SendCertificates sendCertificates( void ); /*! \ingroup groupConfigSign \brief Specifies whether email should be automatically signed, signed after confirmation, signed after confirmation for each part or not signed at all. */ void setSignEmail( SignEmail ); /*! \ingroup groupConfigSign \brief Returns whether email should be automatically signed, signed after confirmation, signed after confirmation for each part or not signed at all. */ SignEmail signEmail( void ); /*! \ingroup groupConfigSign \brief Specifies whether sent email messages should be stored with or without their signatures. */ void setSaveSentSignatures( bool ); /*! \ingroup groupConfigSign \brief Returns whether sent email messages should be stored with or without their signatures. */ bool saveSentSignatures( void ); /*! \ingroup groupConfigSign \brief Specifies whether a warning should be emitted if any of the certificates involved in the signing process expires in the near future. */ void setCertificateExpiryNearWarning( bool ); /*! \ingroup groupConfigSign \brief Returns whether a warning should be emitted if any of the certificates involved in the signing process expires in the near future. */ bool certificateExpiryNearWarning( void ); /*! \ingroup groupConfigSign \brief Specifies whether a warning should be emitted if the email address of the sender is not contained in the certificate. */ void setWarnNoCertificate( bool ); /*! \ingroup groupConfigSign \brief Returns whether a warning should be emitted if the email address of the sender is not contained in the certificate. */ bool warnNoCertificate( void ); /*! \ingroup groupConfigSign \brief Specifies how often the PIN is requested when accessing the secret signature key. */ void setNumPINRequests( PinRequests ); /*! \ingroup groupConfigSign \brief Returns how often the PIN is requested when accessing the secret signature key. */ PinRequests numPINRequests( void ); /*! \ingroup groupConfigSign \brief Specifies whether the certificate path should be followed to the root certificate or whether locally stored certificates may be used. */ void setCheckSignatureCertificatePathToRoot( bool ); /*! \ingroup groupConfigSign \brief Returns whether the certificate path should be followed to the root certificate or whether locally stored certificates may be used. */ bool checkSignatureCertificatePathToRoot( void ); /*! \ingroup groupConfigSign \brief Specifies whether certificate revocation lists should be used. */ void setSignatureUseCRLs( bool ); /*! \ingroup groupConfigSign \brief Returns whether certificate revocation lists should be used. */ bool signatureUseCRLs( void ); /*! \ingroup groupConfigSign \brief Specifies whether a warning should be emitted if any of the certificates involved in the signing process expires in the near future. */ void setSignatureCRLExpiryNearWarning( bool ); /*! \ingroup groupConfigSign \brief Returns whether a warning should be emitted if any of the certificates involved in the signing process expires in the near future. */ bool signatureCRLExpiryNearWarning( void ); /*! \ingroup groupConfigSign \brief Specifies the number of days which a certificate must be valid before it is considered to expire in the near future. */ void setSignatureCRLNearExpiryInterval( int ); /*! \ingroup groupConfigSign \brief Returns the number of days which a certificate must be valid before it is considered to expire in the near future. */ int signatureCRLNearExpiryInterval( void ); /*! \ingroup groupConfigCrypt \brief This function returns an XML representation of a configuration dialog for configuring encryption handling. The syntax is that of .ui files as specified in the Imhotep documentation. This function does not execute or show the dialog in any way; this is up to the MUA. Also, what the MUA makes of the information provided highly depends on the MUA itself. A GUI-based MUA will probably create a dialog window (possibly integrated into an existing configuration dialog in the application), while a terminal-based MUA might generate a series of questions or a terminal based menu selection. */ const char* encryptionConfigurationDialog( void ); /*! \ingroup groupConfigCrypt \brief This function returns an XML representation of a configuration dialog for selecting an encryption algorithm. This will typically be used when the user wants to select an encryption algorithm for one specific message only; the defaults are set in the dialog returned by encryptionConfigurationDialog(). */ const char* encryptionAlgorithmDialog( void ); /*! \ingroup groupConfigCrypt \brief This function returns an XML representation of a configuration dialog for selecting whether an email message and its attachments should be encrypted. This will typically be used when the user wants to select an encryption key for one specific message only; the defaults are set in the dialog returned by encryptionConfigurationDialog(). */ const char* encryptionHandlingDialog( void ); /*! \ingroup groupConfigCrypt \brief This function returns an XML representation of a dialog that lets the user select the certificate to use for encrypting. If it was not possible to determine the correct certificate from the information in the email message, the user is presented with a list of possible certificates to choose from. If a unique certificate was found, this is presented to the user, who needs to confirm the selection of the certificate. This procedure is repeated for each recipient of the email message. */ const char* encryptionReceiverDialog( void ); /*! \ingroup groupConfigCrypt \brief Sets the algorithm used for encrypting. */ void setEncryptionAlgorithm( EncryptionAlgorithm ); /*! \ingroup groupConfigCrypt \brief Returns the algorithm used for encrypting. */ EncryptionAlgorithm encryptionAlgorithm( void ); /*! \ingroup groupConfigCrypt \brief Specifies whether email should be automatically encrypted, encrypted after confirmation, encrypted after confirmation for each part or not encrypted at all. */ void setEncryptEmail( EncryptEmail ); /*! \ingroup groupConfigCrypt \brief Returns whether email should be automatically encrypted, encrypted after confirmation, encrypted after confirmation for each part or not encrypted at all. */ EncryptEmail encryptEmail( void ); /*! \ingroup groupConfigCrypt \brief Specifies whether encrypted email messages should be stored encrypted or decrypted. */ void setSaveMessagesEncrypted( bool ); /*! \ingroup groupConfigCrypt \brief Returns whether encrypted email messages should be stored encrypted or decrypted. */ bool saveMessagesEncrypted( void ); /*! \ingroup groupConfigCrypt \brief Specifies whether the certificate path should be followed to the root certificate or whether locally stored certificates may be used. */ void setCheckEncryptionCertificatePathToRoot( bool ); /*! \ingroup groupConfigCrypt \brief Returns whether the certificate path should be followed to the root certificate or whether locally stored certificates may be used. */ bool checkEncryptionCertificatePathToRoot( void ); /*! \ingroup groupConfigCrypt \brief Specifies whether certificate revocation lists should be used. */ void setEncryptionUseCRLs( bool ); /*! \ingroup groupConfigCrypt \brief Returns whether certificate revocation lists should be used. */ bool encryptionUseCRLs( void ); /*! \ingroup groupConfigCrypt \brief Specifies whether a warning should be emitted if any of the certificates involved in the signing process expires in the near future. */ void setEncryptionCRLExpiryNearWarning( bool ); /*! \ingroup groupConfigCrypt \brief Returns whether a warning should be emitted if any of the certificates involved in the signing process expires in the near future. */ bool encryptionCRLExpiryNearWarning( void ); /*! \ingroup groupConfigCrypt \brief Specifies the number of days which a certificate must be valid before it is considered to expire in the near future. */ void setEncryptionCRLNearExpiryInterval( int ); /*! \ingroup groupConfigCrypt \brief Returns the number of days which a certificate must be valid before it is considered to expire in the near future. */ int encryptionCRLNearExpiryInterval( void ); /*! \ingroup groupConfigDir \brief This function returns an XML representation of a configuration dialog for selecting a directory server. */ const char* directoryServiceConfigurationDialog( void ); /*! \ingroup groupConfigDir \brief Lets you configure how certificates and certificate revocation lists are retrieved (both locally and from directory services). Will mainly be used for restoring configuration data; interactive configuration will be done via the configuration dialog returned by \c directoryServiceConfigurationDialog(). */ void appendDirectoryServer( const char* servername, int port, const char* description ); /*! \ingroup groupConfigDir */ struct DirectoryServer { const char* servername; int port; const char* description; }; /*! \ingroup groupConfigDir \brief Specifies a list of directory servers. Will mainly be used for restoring configuration data; interactive configuration will be done via the configuration dialog returned by \c directoryServiceConfigurationDialog(). */ void setDirectoryServers( struct DirectoryServer[], unsigned int size ); /*! \ingroup groupConfigDir \brief Returns the list of directory servers. Will mainly be used for saving configuration data; interactive configuration will be done via the configuration dialog returned by \c directoryServiceConfigurationDialog(). */ struct DirectoryServer* directoryServers( int* numServers ); /*! \ingroup groupConfigDir \brief Specifies whether certificates should be retrieved from a directory server, only locally, or both. */ void setCertificateSource( CertificateSource ); /*! \ingroup groupConfigDir \brief Returns whether certificates should be retrieved from a directory server, only locally, or both. */ CertificateSource certificateSource( void ); /*! \ingroup groupConfigDir \brief Specifies whether certificates should be retrieved from a directory server, only locally, or both. */ void setCRLSource( CertificateSource ); /*! \ingroup groupConfigDir \brief Returns whether certificates should be retrieved from a directory server, only locally, or both. */ CertificateSource crlSource( void ); /*! \ingroup groupCertHand \brief Returns \c true if and only if the certificates in the certificate chain starting at \c certificate are valid. If \c level is non-null, the parameter contains the degree of trust on a backend-specific scale. In an X.509 implementation, this will either be \c 1 (valid up to the root certificate) or \c 0 (not valid up to the root certificate). */ bool certificateValidity( const char* certificate, int* level ); /*! \ingroup groupSignAct \brief Signs a message \c cleartext and returns in \c ciphertext the message including signature. The signature role is specified by \c certificate. If \c certificate is \c NULL, the default certificate is used. */ bool signMessage( const char* cleartext, const char** ciphertext, const char* certificate ); /*! \ingroup groupSignAct Dummy!! To be replaced by real structure information... */ struct SignatureMetaData { int data; }; /*! \ingroup groupSignAct \brief Checks whether the signature of a message is valid. \c ciphertext specifies the message as it was received by the MUA, \c cleartext is the message with the signature(s) removed. Depending on the configuration, MUAs might not need to use this. If \c sigmeta is non-null, the \c SignatureMetaData object pointed to will contain meta information about the signature after the function call. */ bool checkMessageSignature( const char* ciphertext, const char** cleartext, struct SignatureMetaData* sigmeta ); /*! \ingroup groupSignAct \brief Stores the certificates that follow with the message \c ciphertext locally. */ bool storeCertificatesFromMessage( const char* ciphertext ); /*! \ingroup groupCryptAct \brief Encrypts an email message in \c cleartext according to the current settings (algorithm, etc.) and returns it in \c ciphertext. If the message could be encrypted, the function returns \c true, otherwise \c false. */ bool encryptMessage( const char* cleartext, const char** ciphertext ); /*! \ingroup groupCryptAct \brief Combines the functionality of \c encryptMessage() and \c signMessage(). If \c certificate is \c NULL, the default certificate will be used. If \c sigmeta is non-null, the \c SignatureMetaData object pointed to will contain meta information about the signature after the function call. */ bool encryptAndSignMessage( const char* cleartext, const char** ciphertext, const char* certificate, struct SignatureMetaData* sigmeta ); /*! \ingroup groupCryptAct \brief Tries to decrypt an email message \c ciphertext and returns the decrypted message in \c cleartext. The \c certificate is used for decryption. If the message could be decrypted, the function returns \c true, otherwise \c false. */ bool decryptMessage( const char* ciphertext, const char** cleartext, const char* certificate ); /*! \ingroup groupCryptAct \brief Combines the functionality of \c checkMessageSignature() and \c decryptMessage(). If \c certificate is \c NULL, the default certificate will be used. If \c sigmeta is non-null, the \c SignatureMetaData object pointed to will contain meta information about the signature after the function call. */ bool decryptAndCheckMessage( const char* ciphertext, const char** cleartext, const char* certificate, struct SignatureMetaData* sigmeta ); /*! \ingroup groupCertAct \brief This function returns an XML representation of a dialog that can be used to fill in the data for requesting a certificate (which in turn is done with the function \c requestCertificate() described next. */ const char* requestCertificateDialog( void ); /*! \ingroup groupCertAct \brief Generates a prototype certificate with the data provided in the first four parameters and sends it via email to the CA specified in \c ca_address. */ bool requestDecentralCertificate( const char* name, const char* email, const char* organization, const char* department, const char* ca_address ); /*! \ingroup groupCertAct \brief Requests a certificate in a PSE from the CA specified in \c ca_address. */ bool requestCentralCertificateAndPSE( const char* name, const char* email, const char* organization, const char* department, const char* ca_address ); /*! \ingroup groupCertAct \brief Creates a local PSE. */ bool createPSE( void ); /*! \ingroup groupCertAct \brief Parses and adds a certificate returned by a CA upon request with \c requestDecentralCertificate() or \c requestCentralCertificate(). If the certificate was requested with \c requestCentralCertificate(), the certificate returned will come complete with a PSE which is also registered with this method. */ bool registerCertificate( const char* ); /*! \ingroup groupCertAct \brief Requests the prolongation of the certificate \c certificate from the CA \c ca_address. */ bool requestCertificateProlongation( const char* certificate, const char* ca_address ); /*! \ingroup groupCertAct \brief Returns an HTML 2-formatted string that describes the certificate chain of the user's certificate. Data displayed is at least the issuer of the certificate, the serial number of the certificate, the owner of the certificate, the checksum of the certificate, the validity duration of the certificate, the usage of the certificate, and the contained email addresses, if any. */ const char* certificateChain( void ); /*! \ingroup groupCertAct \brief Deletes the specified user certificate from the current PSE. */ bool deleteCertificate( const char* certificate ); /*! \ingroup groupCertAct \brief Archives the specified user certificate in the current PSE. The certificate cannot be used any longer after this operation unless it is unarchived. */ bool archiveCertificate( const char* certificate ); /*! \ingroup groupCRLAct \brief Returns a HTML 2-formatted string that describes the CRL, suitable for display in the MUA. */ const char* displayCRL( void ); /*! \ingroup groupCRLAct \brief Manually update the CRL. CRLs will also be automatically updated on demand by the backend. If there is a local version of a CRL saved, it will be overwritten with the new CRL from the CA. */ void updateCRL( void ); #ifdef __cplusplus } #endif #endif /*CRYPTPLUG_H*/