/**

 * @file certificate.h Public-Key Certificate API

 * @ingroup core

 * @see @ref certificate-signals

 * @since 2.2.0

 */

/*

 *

 * purple

 *

 * Purple is the legal property of its developers, whose names are too numerous

 * to list here.  Please refer to the COPYRIGHT file distributed with this

 * source distribution.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program 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., 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA

 */

#ifndef _PURPLE_CERTIFICATE_H

#define _PURPLE_CERTIFICATE_H

#include <time.h>

#include <glib.h>

#ifdef __cplusplus

extern "C" {

#endif /* __cplusplus */

typedef enum

{

	PURPLE_CERTIFICATE_INVALID = 0,

	PURPLE_CERTIFICATE_VALID = 1

} PurpleCertificateVerificationStatus;

typedef struct _PurpleCertificate PurpleCertificate;

typedef struct _PurpleCertificatePool PurpleCertificatePool;

typedef struct _PurpleCertificateScheme PurpleCertificateScheme;

typedef struct _PurpleCertificateVerifier PurpleCertificateVerifier;

typedef struct _PurpleCertificateVerificationRequest PurpleCertificateVerificationRequest;

/**

 * Callback function for the results of a verification check

 * @param st       Status code

 * @param userdata User-defined data

 */

typedef void (*PurpleCertificateVerifiedCallback)

		(PurpleCertificateVerificationStatus st,

		 gpointer userdata);

/** A certificate instance

 *

 *  An opaque data structure representing a single certificate under some

 *  CertificateScheme

 */

struct _PurpleCertificate

{

	/** Scheme this certificate is under */

	PurpleCertificateScheme * scheme;

	/** Opaque pointer to internal data */

	gpointer data;

};

/**

 * Database for retrieval or storage of Certificates

 *

 * More or less a hash table; all lookups and writes are controlled by a string

 * key.

 */

struct _PurpleCertificatePool

{

	/** Scheme this Pool operates for */

	gchar *scheme_name;

	/** Internal name to refer to the pool by */

	gchar *name;

	/** User-friendly name for this type

	 *  ex: N_("SSL Servers")

	 *  When this is displayed anywhere, it should be i18ned

	 *  ex: _(pool->fullname)

	 */

	gchar *fullname;

	/** Internal pool data */

	gpointer data;

	/**

	 * Set up the Pool's internal state

	 *

	 * Upon calling purple_certificate_register_pool() , this function will

	 * be called. May be NULL.

	 * @return TRUE if the initialization succeeded, otherwise FALSE

	 */

	gboolean (* init)(void);

	/**

	 * Uninit the Pool's internal state

	 *

	 * Will be called by purple_certificate_unregister_pool() . May be NULL

	 */

	void (* uninit)(void);

	/** Check for presence of a certificate in the pool using unique ID */

	gboolean (* cert_in_pool)(const gchar *id);

	/** Retrieve a PurpleCertificate from the pool */

	PurpleCertificate * (* get_cert)(const gchar *id);

	/** Add a certificate to the pool. Must overwrite any other

	 *  certificates sharing the same ID in the pool.

	 *  @return TRUE if the operation succeeded, otherwise FALSE

	 */

	gboolean (* put_cert)(const gchar *id, PurpleCertificate *crt);

	/** Delete a certificate from the pool */

	gboolean (* delete_cert)(const gchar *id);

	/** Returns a list of IDs stored in the pool */

	GList * (* get_idlist)(void);

	void (*_purple_reserved1)(void);

	void (*_purple_reserved2)(void);

	void (*_purple_reserved3)(void);

	void (*_purple_reserved4)(void);

};

/** A certificate type

 *

 *  A CertificateScheme must implement all of the fields in the structure,

 *  and register it using purple_certificate_register_scheme()

 *

 *  There may be only ONE CertificateScheme provided for each certificate

 *  type, as specified by the "name" field.

 */

struct _PurpleCertificateScheme

{

	/** Name of the certificate type

	 *  ex: "x509", "pgp", etc.

	 *  This must be globally unique - you may not register more than one

	 *  CertificateScheme of the same name at a time.

	 */

	gchar * name;

	/** User-friendly name for this type

	 *  ex: N_("X.509 Certificates")

	 *  When this is displayed anywhere, it should be i18ned

	 *  ex: _(scheme->fullname)

	 */

	gchar * fullname;

	/** Imports a certificate from a file

	 *

	 *  @param filename   File to import the certificate from

	 *  @return           Pointer to the newly allocated Certificate struct

	 *                    or NULL on failure.

	 */

	PurpleCertificate * (* import_certificate)(const gchar * filename);

	/**

	 * Exports a certificate to a file

	 *

	 * @param filename    File to export the certificate to

	 * @param crt         Certificate to export

	 * @return TRUE if the export succeeded, otherwise FALSE

	 * @see purple_certificate_export()

	 */

	gboolean (* export_certificate)(const gchar *filename, PurpleCertificate *crt);

	/**

	 * Duplicates a certificate

	 *

	 * Certificates are generally assumed to be read-only, so feel free to

	 * do any sort of reference-counting magic you want here. If this ever

	 * changes, please remember to change the magic accordingly.

	 * @return Reference to the new copy

	 */

	PurpleCertificate * (* copy_certificate)(PurpleCertificate *crt);

	/** Destroys and frees a Certificate structure

	 *

	 *  Destroys a Certificate's internal data structures and calls

	 *  free(crt)

	 *

	 *  @param crt  Certificate instance to be destroyed. It WILL NOT be

	 *              destroyed if it is not of the correct

	 *              CertificateScheme. Can be NULL

	 */

	void (* destroy_certificate)(PurpleCertificate * crt);

	/** Find whether "crt" has a valid signature from issuer "issuer"

	 *  @see purple_certificate_signed_by() */

	gboolean (*signed_by)(PurpleCertificate *crt, PurpleCertificate *issuer);

	/**

	 * Retrieves the certificate public key fingerprint using SHA1

	 *

	 * @param crt   Certificate instance

	 * @return Binary representation of SHA1 hash - must be freed using

	 *         g_byte_array_free()

	 */

	GByteArray * (* get_fingerprint_sha1)(PurpleCertificate *crt);

	/**

	 * Retrieves a unique certificate identifier

	 *

	 * @param crt   Certificate instance

	 * @return Newly allocated string that can be used to uniquely

	 *         identify the certificate.

	 */

	gchar * (* get_unique_id)(PurpleCertificate *crt);

	/**

	 * Retrieves a unique identifier for the certificate's issuer

	 *

	 * @param crt   Certificate instance

	 * @return Newly allocated string that can be used to uniquely

	 *         identify the issuer's certificate.

	 */

	gchar * (* get_issuer_unique_id)(PurpleCertificate *crt);

	/**

	 * Gets the certificate subject's name

	 *

	 * For X.509, this is the "Common Name" field, as we're only using it

	 * for hostname verification at the moment

	 *

	 * @see purple_certificate_get_subject_name()

	 *

	 * @param crt   Certificate instance

	 * @return Newly allocated string with the certificate subject.

	 */

	gchar * (* get_subject_name)(PurpleCertificate *crt);

	/**

	 * Check the subject name against that on the certificate

	 * @see purple_certificate_check_subject_name()

	 * @return TRUE if it is a match, else FALSE

	 */

	gboolean (* check_subject_name)(PurpleCertificate *crt, const gchar *name);

	/** Retrieve the certificate activation/expiration times */

	gboolean (* get_times)(PurpleCertificate *crt, time_t *activation, time_t *expiration);

	void (*_purple_reserved1)(void);

	void (*_purple_reserved2)(void);

	void (*_purple_reserved3)(void);

	void (*_purple_reserved4)(void);

};

/** A set of operations used to provide logic for verifying a Certificate's

 *  authenticity.

 *

 * A Verifier provider must fill out these fields, then register it using

 * purple_certificate_register_verifier()

 *

 * The (scheme_name, name) value must be unique for each Verifier - you may not

 * register more than one Verifier of the same name for each Scheme

 */

struct _PurpleCertificateVerifier

{

	/** Name of the scheme this Verifier operates on

	 *

	 * The scheme will be looked up by name when a Request is generated

	 * using this Verifier

	 */

	gchar *scheme_name;

	/** Name of the Verifier - case insensitive */

	gchar *name;

	/**

	 * Start the verification process

	 *

	 * To be called from purple_certificate_verify once it has

	 * constructed the request. This will use the information in the

	 * given VerificationRequest to check the certificate and callback

	 * the requester with the verification results.

	 *

	 * @param vrq      Request to process

	 */

	void (* start_verification)(PurpleCertificateVerificationRequest *vrq);

	/**

	 * Destroy a completed Request under this Verifier

	 * The function pointed to here is only responsible for cleaning up

	 * whatever PurpleCertificateVerificationRequest::data points to.

	 * It should not call free(vrq)

	 *

	 * @param vrq       Request to destroy

	 */

	void (* destroy_request)(PurpleCertificateVerificationRequest *vrq);

	void (*_purple_reserved1)(void);

	void (*_purple_reserved2)(void);

	void (*_purple_reserved3)(void);

	void (*_purple_reserved4)(void);

};

/** Structure for a single certificate request

 *

 *  Useful for keeping track of the state of a verification that involves

 *  several steps

 */

struct _PurpleCertificateVerificationRequest

{

	/** Reference to the verification logic used */

	PurpleCertificateVerifier *verifier;

	/** Reference to the scheme used.

	 *

	 * This is looked up from the Verifier when the Request is generated

	 */

	PurpleCertificateScheme *scheme;

	/**

	 * Name to check that the certificate is issued to

	 *

	 * For X.509 certificates, this is the Common Name

	 */

	gchar *subject_name;

	/** List of certificates in the chain to be verified (such as that returned by purple_ssl_get_peer_certificates )

	 *

	 * This is most relevant for X.509 certificates used in SSL sessions.

	 * The list order should be: certificate, issuer, issuer's issuer, etc.

	 */

	GList *cert_chain;

	/** Internal data used by the Verifier code */

	gpointer data;

	/** Function to call with the verification result */

	PurpleCertificateVerifiedCallback cb;

	/** Data to pass to the post-verification callback */

	gpointer cb_data;

};

/*****************************************************************************/

/** @name Certificate Verification Functions                                 */

/*****************************************************************************/

/*@{*/

/**

 * Constructs a verification request and passed control to the specified Verifier

 *

 * It is possible that the callback will be called immediately upon calling

 * this function. Plan accordingly.

 *

 * @param verifier      Verification logic to use.

 *                      @see purple_certificate_find_verifier()

 *

 * @param subject_name  Name that should match the first certificate in the

 *                      chain for the certificate to be valid. Will be strdup'd

 *                      into the Request struct

 *

 * @param cert_chain    Certificate chain to check. If there is more than one

 *                      certificate in the chain (X.509), the peer's

 *                      certificate comes first, then the issuer/signer's

 *                      certificate, etc. The whole list is duplicated into the

 *                      Request struct.

 *

 * @param cb            Callback function to be called with whether the

 *                      certificate was approved or not.

 * @param cb_data       User-defined data for the above.

 */

void

purple_certificate_verify (PurpleCertificateVerifier *verifier,

			   const gchar *subject_name, GList *cert_chain,

			   PurpleCertificateVerifiedCallback cb,

			   gpointer cb_data);

/**

 * Completes and destroys a VerificationRequest

 *

 * @param vrq           Request to conclude

 * @param st            Success/failure code to pass to the request's

 *                      completion callback.

 */

void

purple_certificate_verify_complete(PurpleCertificateVerificationRequest *vrq,

				   PurpleCertificateVerificationStatus st);

/*@}*/

/*****************************************************************************/

/** @name Certificate Functions                                              */

/*****************************************************************************/

/*@{*/

/**

 * Makes a duplicate of a certificate

 *

 * @param crt        Instance to duplicate

 * @return Pointer to new instance

 */

PurpleCertificate *

purple_certificate_copy(PurpleCertificate *crt);

/**

 * Duplicates an entire list of certificates

 *

 * @param crt_list   List to duplicate

 * @return New list copy

 */

GList *

purple_certificate_copy_list(GList *crt_list);

/**

 * Destroys and free()'s a Certificate

 *

 * @param crt        Instance to destroy. May be NULL.

 */

void

purple_certificate_destroy (PurpleCertificate *crt);

/**

 * Destroy an entire list of Certificate instances and the containing list

 *

 * @param crt_list   List of certificates to destroy. May be NULL.

 */

void

purple_certificate_destroy_list (GList * crt_list);

/**

 * Check whether 'crt' has a valid signature made by 'issuer'

 *

 * @param crt        Certificate instance to check signature of

 * @param issuer     Certificate thought to have signed 'crt'

 *

 * @return TRUE if 'crt' has a valid signature made by 'issuer',

 *         otherwise FALSE

 * @todo Find a way to give the reason (bad signature, not the issuer, etc.)

 */

gboolean

purple_certificate_signed_by(PurpleCertificate *crt, PurpleCertificate *issuer);

/**

 * Check that a certificate chain is valid and, if not, the failing certificate.

 *

 * Uses purple_certificate_signed_by() to verify that each PurpleCertificate

 * in the chain carries a valid signature from the next. A single-certificate

 * chain is considered to be valid.

 *

 * @param chain      List of PurpleCertificate instances comprising the chain,

 *                   in the order certificate, issuer, issuer's issuer, etc.

 * @param failing    A pointer to a PurpleCertificate*. If not NULL, if the

 *                   chain fails to validate, this will be set to the

 *                   certificate whose signature could not be validated.

 * @return TRUE if the chain is valid. See description.

 *

 * @since 2.6.0

 * @deprecated  This function will become

 *              purple_certificate_check_signature_chain in 3.0.0

 */

gboolean

purple_certificate_check_signature_chain_with_failing(GList *chain,

		PurpleCertificate **failing);

/**

 * Check that a certificate chain is valid

 *

 * Uses purple_certificate_signed_by() to verify that each PurpleCertificate

 * in the chain carries a valid signature from the next. A single-certificate

 * chain is considered to be valid.

 *

 * @param chain      List of PurpleCertificate instances comprising the chain,

 *                   in the order certificate, issuer, issuer's issuer, etc.

 * @return TRUE if the chain is valid. See description.

 * @todo Specify which certificate in the chain caused a failure

 * @deprecated  This function will be removed in 3.0.0 and replaced with

 *              purple_certificate_check_signature_chain_with_failing

 */

gboolean

purple_certificate_check_signature_chain(GList *chain);

/**

 * Imports a PurpleCertificate from a file

 *

 * @param scheme      Scheme to import under

 * @param filename    File path to import from

 * @return Pointer to a new PurpleCertificate, or NULL on failure

 */

PurpleCertificate *

purple_certificate_import(PurpleCertificateScheme *scheme, const gchar *filename);

/**

 * Exports a PurpleCertificate to a file

 *

 * @param filename    File to export the certificate to

 * @param crt         Certificate to export

 * @return TRUE if the export succeeded, otherwise FALSE

 */

gboolean

purple_certificate_export(const gchar *filename, PurpleCertificate *crt);

/**

 * Retrieves the certificate public key fingerprint using SHA1.

 *

 * @param crt        Certificate instance

 * @return Binary representation of the hash. You are responsible for free()ing

 *         this.

 * @see purple_base16_encode_chunked()

 */

GByteArray *

purple_certificate_get_fingerprint_sha1(PurpleCertificate *crt);

/**

 * Get a unique identifier for the certificate

 *

 * @param crt        Certificate instance

 * @return String representing the certificate uniquely. Must be g_free()'ed

 */

gchar *

purple_certificate_get_unique_id(PurpleCertificate *crt);

/**

 * Get a unique identifier for the certificate's issuer

 *

 * @param crt        Certificate instance

 * @return String representing the certificate's issuer uniquely. Must be

 *         g_free()'ed

 */

gchar *

purple_certificate_get_issuer_unique_id(PurpleCertificate *crt);

/**

 * Gets the certificate subject's name

 *

 * For X.509, this is the "Common Name" field, as we're only using it

 * for hostname verification at the moment

 *

 * @param crt   Certificate instance

 * @return Newly allocated string with the certificate subject.

 */

gchar *

purple_certificate_get_subject_name(PurpleCertificate *crt);

/**

 * Check the subject name against that on the certificate

 * @param crt   Certificate instance

 * @param name  Name to check.

 * @return TRUE if it is a match, else FALSE

 */

gboolean

purple_certificate_check_subject_name(PurpleCertificate *crt, const gchar *name);

/**

 * Get the expiration/activation times.

 *

 * @param crt          Certificate instance

 * @param activation   Reference to store the activation time at. May be NULL

 *                     if you don't actually want it.

 * @param expiration   Reference to store the expiration time at. May be NULL

 *                     if you don't actually want it.

 * @return TRUE if the requested values were obtained, otherwise FALSE.

 */

gboolean

purple_certificate_get_times(PurpleCertificate *crt, time_t *activation, time_t *expiration);

/*@}*/

/*****************************************************************************/

/** @name Certificate Pool Functions                                         */

/*****************************************************************************/

/*@{*/

/**

 * Helper function for generating file paths in ~/.purple/certificates for

 * CertificatePools that use them.

 *

 * All components will be escaped for filesystem friendliness.

 *

 * @param pool   CertificatePool to build a path for

 * @param id     Key to look up a Certificate by. May be NULL.

 * @return A newly allocated path of the form

 *         ~/.purple/certificates/scheme_name/pool_name/unique_id

 */

gchar *

purple_certificate_pool_mkpath(PurpleCertificatePool *pool, const gchar *id);

/**

 * Determines whether a pool can be used.

 *

 * Checks whether the associated CertificateScheme is loaded.

 *

 * @param pool   Pool to check

 *

 * @return TRUE if the pool can be used, otherwise FALSE

 */

gboolean

purple_certificate_pool_usable(PurpleCertificatePool *pool);

/**

 * Looks up the scheme the pool operates under

 *

 * @param pool   Pool to get the scheme of

 *

 * @return Pointer to the pool's scheme, or NULL if it isn't loaded.

 * @see purple_certificate_pool_usable()

 */

PurpleCertificateScheme *

purple_certificate_pool_get_scheme(PurpleCertificatePool *pool);

/**

 * Check for presence of an ID in a pool.

 * @param pool   Pool to look in

 * @param id     ID to look for

 * @return TRUE if the ID is in the pool, else FALSE

 */

gboolean

purple_certificate_pool_contains(PurpleCertificatePool *pool, const gchar *id);

/**

 * Retrieve a certificate from a pool.

 * @param pool   Pool to fish in

 * @param id     ID to look up

 * @return Retrieved certificate, or NULL if it wasn't there

 */

PurpleCertificate *

purple_certificate_pool_retrieve(PurpleCertificatePool *pool, const gchar *id);

/**

 * Add a certificate to a pool

 *

 * Any pre-existing certificate of the same ID will be overwritten.

 *

 * @param pool   Pool to add to

 * @param id     ID to store the certificate with

 * @param crt    Certificate to store

 * @return TRUE if the operation succeeded, otherwise FALSE

 */

gboolean

purple_certificate_pool_store(PurpleCertificatePool *pool, const gchar *id, PurpleCertificate *crt);

/**

 * Remove a certificate from a pool

 *

 * @param pool   Pool to remove from

 * @param id     ID to remove

 * @return TRUE if the operation succeeded, otherwise FALSE

 */

gboolean

purple_certificate_pool_delete(PurpleCertificatePool *pool, const gchar *id);

/**

 * Get the list of IDs currently in the pool.

 *

 * @param pool   Pool to enumerate

 * @return GList pointing to newly-allocated id strings. Free using

 *         purple_certificate_pool_destroy_idlist()

 */

GList *

purple_certificate_pool_get_idlist(PurpleCertificatePool *pool);

/**

 * Destroys the result given by purple_certificate_pool_get_idlist()

 *

 * @param idlist ID List to destroy

 */

void

purple_certificate_pool_destroy_idlist(GList *idlist);

/*@}*/

/*****************************************************************************/

/** @name Certificate Subsystem API                                          */

/*****************************************************************************/

/*@{*/

/**

 * Initialize the certificate system

 */

void

purple_certificate_init(void);

/**

 * Un-initialize the certificate system

 */

void

purple_certificate_uninit(void);

/**

 * Get the Certificate subsystem handle for signalling purposes

 */

gpointer

purple_certificate_get_handle(void);

/** Look up a registered CertificateScheme by name

 * @param name   The scheme name. Case insensitive.

 * @return Pointer to the located Scheme, or NULL if it isn't found.

 */

PurpleCertificateScheme *

purple_certificate_find_scheme(const gchar *name);

/**

 * Get all registered CertificateSchemes

 *

 * @return GList pointing to all registered CertificateSchemes . This value

 *         is owned by libpurple

 */

GList *

purple_certificate_get_schemes(void);

/** Register a CertificateScheme with libpurple

 *

 * No two schemes can be registered with the same name; this function enforces

 * that.

 *

 * @param scheme  Pointer to the scheme to register.

 * @return TRUE if the scheme was successfully added, otherwise FALSE

 */

gboolean

purple_certificate_register_scheme(PurpleCertificateScheme *scheme);

/** Unregister a CertificateScheme from libpurple

 *

 * @param scheme    Scheme to unregister.

 *                  If the scheme is not registered, this is a no-op.

 *

 * @return TRUE if the unregister completed successfully

 */

gboolean

purple_certificate_unregister_scheme(PurpleCertificateScheme *scheme);

/** Look up a registered PurpleCertificateVerifier by scheme and name

 * @param scheme_name  Scheme name. Case insensitive.

 * @param ver_name     The verifier name. Case insensitive.

 * @return Pointer to the located Verifier, or NULL if it isn't found.

 */

PurpleCertificateVerifier *

purple_certificate_find_verifier(const gchar *scheme_name, const gchar *ver_name);

/**

 * Get the list of registered CertificateVerifiers

 *

 * @return GList of all registered PurpleCertificateVerifier. This value

 *         is owned by libpurple

 */

GList *

purple_certificate_get_verifiers(void);

/**

 * Register a CertificateVerifier with libpurple

 *

 * @param vr     Verifier to register.

 * @return TRUE if register succeeded, otherwise FALSE

 */

gboolean

purple_certificate_register_verifier(PurpleCertificateVerifier *vr);

/**

 * Unregister a CertificateVerifier with libpurple

 *

 * @param vr     Verifier to unregister.

 * @return TRUE if unregister succeeded, otherwise FALSE

 */

gboolean

purple_certificate_unregister_verifier(PurpleCertificateVerifier *vr);

/** Look up a registered PurpleCertificatePool by scheme and name

 * @param scheme_name  Scheme name. Case insensitive.

 * @param pool_name    Pool name. Case insensitive.

 * @return Pointer to the located Pool, or NULL if it isn't found.

 */

PurpleCertificatePool *

purple_certificate_find_pool(const gchar *scheme_name, const gchar *pool_name);

/**

 * Get the list of registered Pools

 *

 * @return GList of all registered PurpleCertificatePool s. This value

 *         is owned by libpurple

 */

GList *

purple_certificate_get_pools(void);

/**

 * Register a CertificatePool with libpurple and call its init function

 *

 * @param pool   Pool to register.

 * @return TRUE if the register succeeded, otherwise FALSE

 */

gboolean

purple_certificate_register_pool(PurpleCertificatePool *pool);

/**

 * Unregister a CertificatePool with libpurple and call its uninit function

 *

 * @param pool   Pool to unregister.

 * @return TRUE if the unregister succeeded, otherwise FALSE

 */

gboolean

purple_certificate_unregister_pool(PurpleCertificatePool *pool);

/*@}*/

/**

 * Displays a window showing X.509 certificate information

 *

 * @param crt    Certificate under an "x509" Scheme

 * @todo Will break on CA certs, as they have no Common Name

 */

void

purple_certificate_display_x509(PurpleCertificate *crt);

/**

 * Add a search path for certificates.

 *

 * @param path   Path to search for certificates.

 */

void purple_certificate_add_ca_search_path(const char *path);