// This file is under GNU General Public License 3.0

 // see LICENSE.txt

 #pragma once

 #ifdef __cplusplus

 extern "C" {

 #endif

 #include <stddef.h>

 #include <stdint.h>

 #include <stdbool.h>

 #include "dynamic_api.h"

 #include "stringlist.h"

 #include "stringpair.h"    

 #include "timestamp.h"

 #define PEP_VERSION "2.0" // protocol version

 #define PEP_OWN_USERID "pEp_own_userId"

 // pEp Engine API

 //  caveat:

 //      Unicode data has to be normalized to NFC before calling

 //      UTF-8 strings are UTF-8 encoded C strings (zero terminated)

 struct _pEpSession;

 typedef struct _pEpSession * PEP_SESSION;

 typedef enum {

     PEP_STATUS_OK                                   = 0,

     PEP_INIT_CANNOT_LOAD_GPGME                      = 0x0110,

     PEP_INIT_GPGME_INIT_FAILED                      = 0x0111,

     PEP_INIT_NO_GPG_HOME                            = 0x0112,

     PEP_INIT_NETPGP_INIT_FAILED                     = 0x0113,

     PEP_INIT_CANNOT_DETERMINE_GPG_VERSION           = 0x0114,

     PEP_INIT_UNSUPPORTED_GPG_VERSION                = 0x0115,

     PEP_INIT_CANNOT_CONFIG_GPG_AGENT                = 0x0116,

     PEP_INIT_SQLITE3_WITHOUT_MUTEX                  = 0x0120,

     PEP_INIT_CANNOT_OPEN_DB                         = 0x0121,

     PEP_INIT_CANNOT_OPEN_SYSTEM_DB                  = 0x0122,

     PEP_KEY_NOT_FOUND                               = 0x0201,

     PEP_KEY_HAS_AMBIG_NAME                          = 0x0202,

     PEP_GET_KEY_FAILED                              = 0x0203,

     PEP_CANNOT_EXPORT_KEY                           = 0x0204,

     PEP_CANNOT_EDIT_KEY                             = 0x0205,

     PEP_KEY_UNSUITABLE                              = 0x0206,

     PEP_CANNOT_FIND_IDENTITY                        = 0x0301,

     PEP_CANNOT_SET_PERSON                           = 0x0381,

     PEP_CANNOT_SET_PGP_KEYPAIR                      = 0x0382,

     PEP_CANNOT_SET_IDENTITY                         = 0x0383,

     PEP_CANNOT_SET_TRUST                            = 0x0384,

     PEP_KEY_BLACKLISTED                             = 0x0385,

     PEP_CANNOT_FIND_PERSON                          = 0x0386,

     PEP_CANNOT_FIND_ALIAS                           = 0x0391,

     PEP_CANNOT_SET_ALIAS                            = 0x0392,

     PEP_UNENCRYPTED                                 = 0x0400,

     PEP_VERIFIED                                    = 0x0401,

     PEP_DECRYPTED                                   = 0x0402,

     PEP_DECRYPTED_AND_VERIFIED                      = 0x0403,

     PEP_DECRYPT_WRONG_FORMAT                        = 0x0404,

     PEP_DECRYPT_NO_KEY                              = 0x0405,

     PEP_DECRYPT_SIGNATURE_DOES_NOT_MATCH            = 0x0406,

     PEP_VERIFY_NO_KEY                               = 0x0407,

     PEP_VERIFIED_AND_TRUSTED                        = 0x0408,

     PEP_CANNOT_REENCRYPT                            = 0x0409,

     PEP_CANNOT_DECRYPT_UNKNOWN                      = 0x04ff,

     PEP_TRUSTWORD_NOT_FOUND                         = 0x0501,

     PEP_TRUSTWORDS_FPR_WRONG_LENGTH                 = 0x0502,

     PEP_TRUSTWORDS_DUPLICATE_FPR                    = 0x0503,

     PEP_CANNOT_CREATE_KEY                           = 0x0601,

     PEP_CANNOT_SEND_KEY                             = 0x0602,

     PEP_PHRASE_NOT_FOUND                            = 0x0701,

     PEP_SEND_FUNCTION_NOT_REGISTERED                = 0x0801,

     PEP_CONTRAINTS_VIOLATED                         = 0x0802,

     PEP_CANNOT_ENCODE                               = 0x0803,

     PEP_SYNC_NO_NOTIFY_CALLBACK                     = 0x0901,

     PEP_SYNC_ILLEGAL_MESSAGE                        = 0x0902,

     PEP_SYNC_NO_INJECT_CALLBACK                     = 0x0903,

     PEP_SEQUENCE_VIOLATED                           = 0x0970,

     PEP_CANNOT_INCREASE_SEQUENCE                    = 0x0971,

     PEP_CANNOT_SET_SEQUENCE_VALUE                   = 0x0972,

     PEP_OWN_SEQUENCE                                = 0x097f,

     PEP_SYNC_STATEMACHINE_ERROR                     = 0x0980,

     PEP_SYNC_NO_TRUST                               = 0x0981,

     PEP_STATEMACHINE_INVALID_STATE                  = 0x0982,

     PEP_STATEMACHINE_INVALID_EVENT                  = 0x0983,

     PEP_STATEMACHINE_INVALID_CONDITION              = 0x0984,

     PEP_STATEMACHINE_INVALID_ACTION                 = 0x0985,

     PEP_STATEMACHINE_INHIBITED_EVENT                = 0x0986,

     PEP_COMMIT_FAILED                               = 0xff01,

     PEP_MESSAGE_CONSUME                             = 0xff02,

     PEP_MESSAGE_IGNORE                              = 0xff03,

     PEP_RECORD_NOT_FOUND                            = -6,

     PEP_CANNOT_CREATE_TEMP_FILE                     = -5,

     PEP_ILLEGAL_VALUE                               = -4,

     PEP_BUFFER_TOO_SMALL                            = -3,

     PEP_OUT_OF_MEMORY                               = -2,

     PEP_UNKNOWN_ERROR                               = -1,

     PEP_VERSION_MISMATCH                            = -7,

 } PEP_STATUS;

 // INIT_STATUS init() - initialize pEpEngine for a thread

 //

 //  parameters:

 //        session (out)   init() allocates session memory and returns a pointer

 //                        as a handle

 //

 //  return value:

 //        PEP_STATUS_OK = 0                 if init() succeeds

 //        PEP_INIT_SQLITE3_WITHOUT_MUTEX    if SQLite3 was compiled with

 //                                            SQLITE_THREADSAFE 0

 //        PEP_INIT_CANNOT_LOAD_GPGME        if libgpgme.dll cannot be found

 //        PEP_INIT_GPGME_INIT_FAILED        if GPGME init fails

 //        PEP_INIT_CANNOT_OPEN_DB           if user's management db cannot be

 //                                            opened

 //        PEP_INIT_CANNOT_OPEN_SYSTEM_DB    if system's management db cannot be

 //                                            opened

 //

 //  caveat:

 //      THE CALLER MUST GUARD THIS CALL EXTERNALLY WITH A MUTEX. release() should

 //      be similarly guarded.

 //

 //      the pointer is valid only if the return value is PEP_STATUS_OK

 //      in other case a NULL pointer will be returned; a valid handle must

 //      be released using release() when it's no longer needed

 //

 //      the caller has to guarantee that the first call to this function

 //      will succeed before further calls can be done

 DYNAMIC_API PEP_STATUS init(PEP_SESSION *session);

 // void release() - release thread session handle

 //

 //  parameters:

 //        session (in)    session handle to release

 //

 //    caveat:

 //        THE CALLER MUST GUARD THIS CALL EXTERNALLY WITH A MUTEX. init() should

 //        be similarly guarded.

 //       

 //        the last release() can be called only when all other release() calls

 //        are done

 DYNAMIC_API void release(PEP_SESSION session);

 // const stringlist_t* get_errorstack(PEP_SESSION) - get the error stack for that session, if any

 //

 //  parameters:

 //        session (in)    session handle

 //

 //    caveat:

 //        To get a useful error stack you have to compile with -DDEBUG_ERRORSTACK

 //        The error stack belongs to the session. Do no not change it!

 DYNAMIC_API const stringlist_t* get_errorstack(PEP_SESSION session);

 // void clear_errorstack(PEP_SESSION) - clear the error stack for that session, if any

 //

 //  parameters:

 //        session (in)    session handle

 //

 DYNAMIC_API void clear_errorstack(PEP_SESSION session);

 // config_passive_mode() - enable passive mode

 //

 //  parameters:

 //      session (in)    session handle

 //      enable (in)     flag if enabled or disabled

 DYNAMIC_API void config_passive_mode(PEP_SESSION session, bool enable);

 // config_unencrypted_subject() - disable subject encryption

 //

 //  parameters:

 //      session (in)    session handle

 //      enable (in)     flag if enabled or disabled

 DYNAMIC_API void config_unencrypted_subject(PEP_SESSION session, bool enable);

 // config_use_only_own_private_keys() - enable passive mode

 //

 //  parameters:

 //      session (in)    session handle

 //      enable (in)     flag if enabled or disabled

 DYNAMIC_API void config_use_only_own_private_keys(PEP_SESSION session, bool enable);

 // config_keep_sync_msg() - do not remove sync messages (for debugging purposes)

 //

 //      session (in)    session handle

 //      enable (in)     flag if enabled or disabled

 DYNAMIC_API void config_keep_sync_msg(PEP_SESSION session, bool enable);

 // config_service_log() - log more for service purposes

 //

 //      session (in)    session handle

 //      enable (in)     flag if enabled or disabled

 DYNAMIC_API void config_service_log(PEP_SESSION session, bool enable);

 // decrypt_and_verify() - decrypt and/or verify a message

 //

 //    parameters:

 //        session (in)    session handle

 //        ctext (in)      cipher text to decrypt and/or verify

 //        csize (in)      size of cipher text

 //        dsigtext (in)   if extant, *detached* signature text for this

 //                        message (or NULL if not)

 //        dsize (in)      size of *detached* signature text for this

 //                        message (0, if no detached sig exists)

 //        ptext (out)     pointer to internal buffer with plain text

 //        psize (out)     size of plain text

 //        keylist (out)   list of key ids which where used to encrypt

 //

 //    return value:

 //        PEP_UNENCRYPTED               message was unencrypted and not signed

 //        PEP_VERIFIED                  message was unencrypted, signature matches

 //        PEP_DECRYPTED                 message is decrypted now, no signature

 //        PEP_DECRYPTED_AND_VERIFIED    message is decrypted now and verified

 //        PEP_DECRYPT_WRONG_FORMAT      message has wrong format to handle

 //        PEP_DECRYPT_NO_KEY            key not available to decrypt and/or verify

 //        PEP_DECRYPT_SIGNATURE_DOES_NOT_MATCH    wrong signature

 //

 //    caveat:

 //        the ownerships of ptext as well as keylist are going to the caller

 //        the caller must use free() (or an Windoze pEp_free()) and

 //        free_stringlist() to free them

 //

 //      if this function failes an error message may be the first element of

 //      keylist and the other elements may be the keys used for encryption

 DYNAMIC_API PEP_STATUS decrypt_and_verify(

         PEP_SESSION session, const char *ctext, size_t csize,

         const char *dsigtext, size_t dsigsize,

         char **ptext, size_t *psize, stringlist_t **keylist

     );

 // verify_text() - verfy plain text with a digital signature

 //

 //  parameters:

 //      session (in)    session handle

 //      text (in)       text to verify

 //      size (in)       size of text

 //      signature (in)  signature text

 //      sig_size (in)   size of signature

 //      keylist (out)   list of key ids which where used to encrypt or NULL on

 //                        error

 //

 //  return value:

 //        PEP_VERIFIED                message was unencrypted, signature matches

 //        PEP_DECRYPT_NO_KEY          key not available to decrypt and/or verify

 //        PEP_DECRYPT_SIGNATURE_DOES_NOT_MATCH    wrong signature

 DYNAMIC_API PEP_STATUS verify_text(

         PEP_SESSION session, const char *text, size_t size,

         const char *signature, size_t sig_size, stringlist_t **keylist

     );

 // encrypt_and_sign() - encrypt and sign a message

 //

 //    parameters:

 //        session (in)    session handle

 //        keylist (in)    list of key ids to encrypt with as C strings

 //        ptext (in)      plain text to decrypt and/or verify

 //        psize (in)      size of plain text

 //        ctext (out)     pointer to internal buffer with cipher text

 //        csize (out)     size of cipher text

 //

 //    return value:

 //        PEP_STATUS_OK = 0            encryption and signing succeeded

 //        PEP_KEY_NOT_FOUND            at least one of the recipient keys

 //                                     could not be found

 //        PEP_KEY_HAS_AMBIG_NAME       at least one of the recipient keys has

 //                                     an ambiguous name

 //        PEP_GET_KEY_FAILED           cannot retrieve key

 //

 //    caveat:

 //      the ownership of ctext is going to the caller

 //      the caller is responsible to free() it (on Windoze use pEp_free())

 //      the first key in keylist is being used to sign the message

 //      this implies there has to be a private key for that keypair

 DYNAMIC_API PEP_STATUS encrypt_and_sign(

         PEP_SESSION session, const stringlist_t *keylist, const char *ptext,

         size_t psize, char **ctext, size_t *csize

     );

 // log_event() - log a user defined event defined by UTF-8 encoded strings into

 // management log

 //

 //    parameters:

 //        session (in)        session handle

 //        title (in)          C string with event name

 //        entity (in)         C string with name of entity which is logging

 //        description (in)    C string with long description for event or NULL if

 //                            omitted

 //        comment (in)        C string with user defined comment or NULL if

 //                            omitted

 //

 //    return value:

 //        PEP_STATUS_OK       log entry created

 DYNAMIC_API PEP_STATUS log_event(

         PEP_SESSION session,

         const char *title,

         const char *entity,

         const char *description,

         const char *comment

     );

 DYNAMIC_API PEP_STATUS log_service(PEP_SESSION session, const char *title,

         const char *entity, const char *description, const char *comment);

 #define _STR_(x) #x

 #define _D_STR_(x) _STR_(x)

 #define S_LINE _D_STR_(__LINE__)

 #define SERVICE_LOG(session, title, entity, desc) \

     log_service((session), (title), (entity), (desc), "service " __FILE__ ":" S_LINE)

 // trustword() - get the corresponding trustword for a 16 bit value

 //

 //    parameters:

 //        session (in)            session handle

 //        value (in)              value to find a trustword for

 //        lang (in)               C string with ISO 639-1 language code

 //        word (out)              pointer to C string with trustword UTF-8 encoded

 //                                NULL if language is not supported or trustword

 //                                wordlist is damaged or unavailable

 //        wsize (out)             length of trustword

 //

 //    return value:

 //        PEP_STATUS_OK            trustword retrieved

 //        PEP_TRUSTWORD_NOT_FOUND  trustword not found

 //

 //    caveat:

 //        the word pointer goes to the ownership of the caller

 //      the caller is responsible to free() it (on Windoze use pEp_free())

 DYNAMIC_API PEP_STATUS trustword(

             PEP_SESSION session, uint16_t value, const char *lang,

             char **word, size_t *wsize

         );

 // trustwords() - get trustwords for a string of hex values of a fingerprint

 //

 //    parameters:

 //        session (in)        session handle

 //        fingerprint (in)    C string with hex values to find trustwords for

 //        lang (in)           C string with ISO 639-1 language code

 //        words (out)         pointer to C string with trustwords UTF-8 encoded,

 //                            separated by a blank each

 //                            NULL if language is not supported or trustword

 //                            wordlist is damaged or unavailable

 //        wsize (out)         length of trustwords string

 //        max_words (in)      only generate a string with max_words;

 //                            if max_words == 0 there is no such limit

 //

 //    return value:

 //        PEP_STATUS_OK            trustwords retrieved

 //        PEP_OUT_OF_MEMORY        out of memory

 //        PEP_TRUSTWORD_NOT_FOUND  at least one trustword not found

 //

 //    caveat:

 //        the word pointer goes to the ownership of the caller

 //      the caller is responsible to free() it (on Windoze use pEp_free())

 //

 //  DON'T USE THIS FUNCTION FROM HIGH LEVEL LANGUAGES!

 //

 //  Better implement a simple one in the adapter yourself using trustword(), and

 //  return a list of trustwords.

 //  This function is provided for being used by C and C++ programs only.

 DYNAMIC_API PEP_STATUS trustwords(

         PEP_SESSION session, const char *fingerprint, const char *lang,

         char **words, size_t *wsize, int max_words

     );

 // TODO: increase versions in pEp.asn1 if rating changes

 typedef enum _PEP_comm_type {

     PEP_ct_unknown = 0,

     // range 0x01 to 0x09: no encryption, 0x0a to 0x0e: nothing reasonable

     PEP_ct_no_encryption = 0x01,                // generic

     PEP_ct_no_encrypted_channel = 0x02,

     PEP_ct_key_not_found = 0x03,

     PEP_ct_key_expired = 0x04,

     PEP_ct_key_revoked = 0x05,

     PEP_ct_key_b0rken = 0x06,

     PEP_ct_my_key_not_included = 0x09,

     PEP_ct_security_by_obscurity = 0x0a,

     PEP_ct_b0rken_crypto = 0x0b,

     PEP_ct_key_too_short = 0x0c,

     PEP_ct_compromised = 0x0e,                  // known compromised connection

     PEP_ct_compromized = 0x0e,                  // deprecated misspelling

     PEP_ct_mistrusted = 0x0f,                   // known mistrusted key

     // range 0x10 to 0x3f: unconfirmed encryption

     PEP_ct_unconfirmed_encryption = 0x10,       // generic

     PEP_ct_OpenPGP_weak_unconfirmed = 0x11,     // RSA 1024 is weak

     PEP_ct_to_be_checked = 0x20,                // generic

     PEP_ct_SMIME_unconfirmed = 0x21,

     PEP_ct_CMS_unconfirmed = 0x22,

     PEP_ct_strong_but_unconfirmed = 0x30,       // generic

     PEP_ct_OpenPGP_unconfirmed = 0x38,          // key at least 2048 bit RSA or EC

     PEP_ct_OTR_unconfirmed = 0x3a,

     // range 0x40 to 0x7f: unconfirmed encryption and anonymization

     PEP_ct_unconfirmed_enc_anon = 0x40,         // generic

     PEP_ct_pEp_unconfirmed = 0x7f,

     PEP_ct_confirmed = 0x80,                    // this bit decides if trust is confirmed

     // range 0x81 to 0x8f: reserved

     // range 0x90 to 0xbf: confirmed encryption

     PEP_ct_confirmed_encryption = 0x90,         // generic

     PEP_ct_OpenPGP_weak = 0x91,                 // RSA 1024 is weak (unused)

     PEP_ct_to_be_checked_confirmed = 0xa0,      //generic

     PEP_ct_SMIME = 0xa1,

     PEP_ct_CMS = 0xa2,

     PEP_ct_strong_encryption = 0xb0,            // generic

     PEP_ct_OpenPGP = 0xb8,                      // key at least 2048 bit RSA or EC

     PEP_ct_OTR = 0xba,

     // range 0xc0 to 0xff: confirmed encryption and anonymization

     PEP_ct_confirmed_enc_anon = 0xc0,           // generic

     PEP_ct_pEp = 0xff

 } PEP_comm_type;

 typedef enum _identity_flags {

     // the first octet flags are app defined settings

     PEP_idf_not_for_sync = 0x0001,   // don't use this identity for sync

     PEP_idf_list = 0x0002,           // identity of list of persons

     // the second octet flags are calculated

     PEP_idf_devicegroup = 0x0100     // identity of a device group member

 } identity_flags;

 typedef unsigned int identity_flags_t;

 // typedef enum _keypair_flags {

 // } keypair_flags;

 typedef unsigned int keypair_flags_t;

 typedef struct _pEp_identity {

     char *address;              // C string with address UTF-8 encoded

     char *fpr;                  // C string with fingerprint UTF-8 encoded

     char *user_id;              // C string with user ID UTF-8 encoded

                                 // user_id MIGHT be set to "pEp_own_userId"

                                 // (use PEP_OWN_USERID preprocessor define)

                                 // if this is own user's identity.

                                 // But it is not REQUIRED to be.

     char *username;             // C string with user name UTF-8 encoded

     PEP_comm_type comm_type;    // type of communication with this ID

     char lang[3];               // language of conversation

                                 // ISO 639-1 ALPHA-2, last byte is 0

     bool me;                    // if this is the local user herself/himself

     identity_flags_t flags;     // identity_flag1 | identity_flag2 | ...

 } pEp_identity;

 typedef struct _identity_list {

     pEp_identity *ident;

     struct _identity_list *next;

 } identity_list;

 // new_identity() - allocate memory and set the string and size fields

 //

 //  parameters:

 //      address (in)        UTF-8 string or NULL 

 //      fpr (in)            UTF-8 string or NULL 

 //      user_id (in)        UTF-8 string or NULL 

 //      username (in)       UTF-8 string or NULL 

 //

 //  return value:

 //      pEp_identity struct or NULL if out of memory

 //

 //  caveat:

 //      the strings are copied; the original strings are still being owned by

 //      the caller

 DYNAMIC_API pEp_identity *new_identity(

         const char *address, const char *fpr, const char *user_id,

         const char *username

     );

 // identity_dup() - allocate memory and duplicate

 //

 //  parameters:

 //      src (in)            identity to duplicate

 //

 //  return value:

 //      pEp_identity struct or NULL if out of memory

 //

 //  caveat:

 //      the strings are copied; the original strings are still being owned by

 //      the caller

 DYNAMIC_API pEp_identity *identity_dup(const pEp_identity *src);

 // free_identity() - free all memory being occupied by a pEp_identity struct

 //

 //  parameters:

 //      identity (in)       struct to release

 //

 //  caveat:

 //      not only the struct but also all string memory referenced by the

 //      struct is being freed; all pointers inside are invalid afterwards

 DYNAMIC_API void free_identity(pEp_identity *identity);

 // get_identity() - get identity information

 //

 //    parameters:

 //        session (in)        session handle

 //        address (in)        C string with communication address, UTF-8 encoded

 //        user_id (in)        unique C string to identify person that identity

 //                            is refering to

 //        identity (out)      pointer to pEp_identity structure with results or

 //                            NULL if failure

 //

 //    caveat:

 //        address and user_id are being copied; the original strings remains in

 //        the ownership of the caller

 //        the resulting pEp_identity structure goes to the ownership of the

 //        caller and has to be freed with free_identity() when not in use any

 //        more

 DYNAMIC_API PEP_STATUS get_identity(

         PEP_SESSION session,

         const char *address,

         const char *user_id,

         pEp_identity **identity

     );

 PEP_STATUS replace_identities_fpr(PEP_SESSION session, 

                                  const char* old_fpr, 

                                  const char* new_fpr); 

 // set_identity() - set identity information

 //

 //    parameters:

 //        session (in)        session handle

 //        identity (in)       pointer to pEp_identity structure

 //

 //    return value:

 //        PEP_STATUS_OK = 0             encryption and signing succeeded

 //        PEP_CANNOT_SET_PERSON         writing to table person failed

 //        PEP_CANNOT_SET_PGP_KEYPAIR    writing to table pgp_keypair failed

 //        PEP_CANNOT_SET_IDENTITY       writing to table identity failed

 //        PEP_COMMIT_FAILED             SQL commit failed

 //

 //    caveat:

 //        address, fpr, user_id and username must be given

 DYNAMIC_API PEP_STATUS set_identity(

         PEP_SESSION session, const pEp_identity *identity

     );

 // get_default own_userid() - get the user_id of the own user

 //

 //    parameters:

 //        session (in)        session handle

 //        userid  (out)       own user id (if it exists)

 //

 //    return value:

 //        PEP_STATUS_OK = 0             userid was found

 //        PEP_CANNOT_FIND_IDENTITY      no own_user found in the DB

 //        PEP_UNKNOWN_ERROR             results were returned, but no ID

 //                                      found (no reason this should ever occur)

 //    caveat:

 //        userid will be NULL if not found; otherwise, returned string

 //        belongs to the caller.

 DYNAMIC_API PEP_STATUS get_default_own_userid(

         PEP_SESSION session, 

         char** userid

     );

 // get_userid_alias_default() - get the default user_id which corresponds

 //                              to an alias

 //    parameters:

 //        session (in)        session handle

 //        alias_id (in)       the user_id which may be an alias for a default id

 //        default_id (out)    the default id for this alias, if the alias

 //                            is in the DB as an alias, else NULL

 //    return value:

 //        PEP_STATUS_OK = 0             userid was found

 //        PEP_CANNOT_FIND_ALIAS         this userid is not listed as an 

 //                                      alias in the DB

 //        PEP_UNKNOWN_ERROR             results were returned, but no ID

 //                                      found (no reason this should ever occur)

 //    caveat:

 //        default_id will be NULL if not found; otherwise, returned string

 //        belongs to the caller.

 //        also, current implementation does NOT check to see if this userid

 //        IS a default.

 DYNAMIC_API PEP_STATUS get_userid_alias_default(

         PEP_SESSION session, 

         const char* alias_id,

         char** default_id);

 // set_userid_alias() - set an alias to correspond to a default id

 //    parameters:

 //        session (in)        session handle

 //        default_id (in)     the default id for this alias. This must

 //                            correspond to the default user_id for an

 //                            entry in the person (user) table.

 //        alias_id (in)       the alias to be set for this default id

 //    return value:

 //        PEP_STATUS_OK = 0             userid was found

 //        PEP_CANNOT_SET_ALIAS          there was an error setting this

 DYNAMIC_API PEP_STATUS set_userid_alias (

         PEP_SESSION session, 

         const char* default_id,

         const char* alias_id);

 // set_device_group() - update own person's device group

 //

 //    parameters:

 //        session (in)        session handle

 //        group_name (in)     new group name

 //

 //    return value:

 //        PEP_STATUS_OK = 0             device group was updated

 //        PEP_CANNOT_SET_PERSON         update failed

 DYNAMIC_API PEP_STATUS set_device_group(

         PEP_SESSION session,

         const char *group_name

     );

 // get_device_group() - get own person's device group

 //

 //    parameters:

 //        session (in)        session handle

 //        group_name (in)     new group name

 //

 //    return value:

 //        PEP_STATUS_OK = 0             couldn't get device group

 //        PEP_RECORD_NOT_FOUND          update failed

 //

 //    caveat:

 //        the ownerships of group_name is going to the caller

 DYNAMIC_API PEP_STATUS get_device_group(

         PEP_SESSION session, 

         char **group_name

     );

 // set_identity_flags() - update identity flags on existing identity

 //

 //    parameters:

 //        session (in)        session handle

 //        identity (in,out)   pointer to pEp_identity structure

 //        flags (in)          new value for flags

 //

 //    return value:

 //        PEP_STATUS_OK = 0             encryption and signing succeeded

 //        PEP_CANNOT_SET_IDENTITY       update of identity failed

 //

 //    caveat:

 //        address and user_id must be given in identity

 DYNAMIC_API PEP_STATUS set_identity_flags(

         PEP_SESSION session,

         pEp_identity *identity,

         identity_flags_t flags

     );

 // unset_identity_flags() - update identity flags on existing identity

 //

 //    parameters:

 //        session (in)        session handle

 //        identity (in,out)   pointer to pEp_identity structure

 //        flags (in)          new value for flags

 //

 //    return value:

 //        PEP_STATUS_OK = 0             encryption and signing succeeded

 //        PEP_CANNOT_SET_IDENTITY       update of identity failed

 //

 //    caveat:

 //        address and user_id must be given in identity

 DYNAMIC_API PEP_STATUS unset_identity_flags(

         PEP_SESSION session,

         pEp_identity *identity,

         identity_flags_t flags

     );

 // mark_as_compromised() - mark key in trust db as compromised

 //

 //    parameters:

 //        session (in)        session handle

 //        fpr (in)            fingerprint of key to mark

 DYNAMIC_API PEP_STATUS mark_as_compromised(

         PEP_SESSION session,

         const char *fpr

     );

 // mark_as_compromized() - deprecated to fix misspelling. Please move to

 //                         mark_as_compromised();

 DYNAMIC_API PEP_STATUS mark_as_compromized(

         PEP_SESSION session,

         const char *fpr

     );

 // generate_keypair() - generate a new key pair and add it to the key ring

 //

 //  parameters:

 //      session (in)            session handle

 //        identity (inout)      pointer to pEp_identity structure

 //

 //    return value:

 //        PEP_STATUS_OK = 0       encryption and signing succeeded

 //        PEP_ILLEGAL_VALUE       illegal values for identity fields given

 //        PEP_CANNOT_CREATE_KEY   key engine is on strike

 //

 //  caveat:

 //      address and username fields must be set to UTF-8 strings

 //      the fpr field must be set to NULL

 //

 //      this function allocates a string and sets set fpr field of identity

 //      the caller is responsible to call free() for that string or use

 //      free_identity() on the struct

 DYNAMIC_API PEP_STATUS generate_keypair(

         PEP_SESSION session, pEp_identity *identity

     );

 // delete_keypair() - delete a public key or a key pair from the key ring

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                C string with key id or fingerprint of the

 //                              public key

 //

 //  return value:

 //      PEP_STATUS_OK = 0       key was successfully deleted

 //      PEP_KEY_NOT_FOUND       key not found

 //      PEP_ILLEGAL_VALUE       not a valid key id or fingerprint

 //      PEP_KEY_HAS_AMBIG_NAME  fpr does not uniquely identify a key

 //      PEP_OUT_OF_MEMORY       out of memory

 DYNAMIC_API PEP_STATUS delete_keypair(PEP_SESSION session, const char *fpr);

 // import_key() - import key from data

 //

 //  parameters:

 //      session (in)            session handle

 //      key_data (in)           key data, i.e. ASCII armored OpenPGP key

 //      size (in)               amount of data to handle

 //      private_keys (out)      list of private keys that have been imported

 //

 //  return value:

 //      PEP_STATUS_OK = 0       key was successfully imported

 //      PEP_OUT_OF_MEMORY       out of memory

 //      PEP_ILLEGAL_VALUE       there is no key data to import

 //

 //  caveat:

 //      private_keys goes to the ownership of the caller

 //      private_keys can be left NULL, it is then ignored

 DYNAMIC_API PEP_STATUS import_key(

         PEP_SESSION session,

         const char *key_data,

         size_t size,

         identity_list **private_keys

     );

 // export_key() - export ascii armored key

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                key id or fingerprint of key

 //      key_data (out)          ASCII armored OpenPGP key

 //      size (out)              amount of data to handle

 //

 //  return value:

 //      PEP_STATUS_OK = 0       key was successfully exported

 //      PEP_OUT_OF_MEMORY       out of memory

 //      PEP_KEY_NOT_FOUND       key not found

 //

 //  caveat:

 //      the key_data goes to the ownership of the caller

 //      the caller is responsible to free() it (on Windoze use pEp_free())

 DYNAMIC_API PEP_STATUS export_key(

         PEP_SESSION session, const char *fpr, char **key_data, size_t *size

     );

 // export_secret_key() - export secret key ascii armored

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                fingerprint of key, at least 16 hex digits

 //      key_data (out)          ASCII armored OpenPGP secret key

 //      size (out)              amount of data to handle

 //

 //  return value:

 //      PEP_STATUS_OK = 0       key was successfully exported

 //      PEP_OUT_OF_MEMORY       out of memory

 //      PEP_KEY_NOT_FOUND       key not found

 //      PEP_CANNOT_EXPORT_KEY   cannot export secret key (i.e. it's on an HKS)

 //

 //  caveat:

 //      the key_data goes to the ownership of the caller

 //      the caller is responsible to free() it (on Windoze use pEp_free())

 //      beware of leaking secret key data - overwrite it in memory after use

 DYNAMIC_API PEP_STATUS export_secret_key(

         PEP_SESSION session, const char *fpr, char **key_data, size_t *size

     );

 // export_secrect_key() - deprecated misspelled function. Please replace with

 //                        export_secret_key

 DYNAMIC_API PEP_STATUS export_secrect_key(

         PEP_SESSION session, const char *fpr, char **key_data, size_t *size

     );

 // recv_key() - update key(s) from keyserver

 //

 //  parameters:

 //      session (in)            session handle

 //      pattern (in)            key id, user id or address to search for as

 //                              UTF-8 string

 DYNAMIC_API PEP_STATUS recv_key(PEP_SESSION session, const char *pattern);

 // find_keys() - find keys in keyring

 //

 //  parameters:

 //      session (in)            session handle

 //      pattern (in)            key id, user id or address to search for as

 //                              UTF-8 string

 //      keylist (out)           list of fingerprints found or NULL on error

 //

 //  caveat:

 //        the ownerships of keylist isgoing to the caller

 //        the caller must use free_stringlist() to free it

 DYNAMIC_API PEP_STATUS find_keys(

         PEP_SESSION session, const char *pattern, stringlist_t **keylist

     );

 // send_key() - send key(s) to keyserver

 //

 //  parameters:

 //      session (in)            session handle

 //      pattern (in)            key id, user id or address to search for as

 //                              UTF-8 string

 DYNAMIC_API PEP_STATUS send_key(PEP_SESSION session, const char *pattern);

 // pEp_free() - free memory allocated by pEp engine

 //

 //  parameters:

 //      p (in)                  pointer to free

 //

 //  The reason for this function is that heap management can be a pretty

 //  complex task with Windoze. This free() version calls the free()

 //  implementation of the C runtime library which was used to build pEp engine,

 //  so you're using the correct heap. For more information, see:

 //  <http://msdn.microsoft.com/en-us/library/windows/desktop/aa366711(v=vs.85).aspx>

 DYNAMIC_API void pEp_free(void *p);

 // get_trust() - get the trust level a key has for a person

 //

 //  parameters:

 //      session (in)            session handle

 //      identity (inout)        user_id and fpr to check as UTF-8 strings (in)

 //                              comm_type as result (out)

 //

 //  this function modifies the given identity struct; the struct remains in

 //  the ownership of the caller

 //  if the trust level cannot be determined identity->comm_type is set

 //  to PEP_ct_unknown

 DYNAMIC_API PEP_STATUS get_trust(PEP_SESSION session, pEp_identity *identity);

 PEP_STATUS set_trust(PEP_SESSION session, 

                      pEp_identity* identity);

 PEP_STATUS update_trust_for_fpr(PEP_SESSION session, 

                                 const char* fpr, 

                                 PEP_comm_type comm_type);

 // least_trust() - get the least known trust level for a key in the database

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                fingerprint of key to check

 //      comm_type (out)         least comm_type as result (out)

 //

 //  if the trust level cannot be determined comm_type is set to PEP_ct_unknown

 DYNAMIC_API PEP_STATUS least_trust(

         PEP_SESSION session,

         const char *fpr,

         PEP_comm_type *comm_type

     );

 // get_key_rating() - get the rating a bare key has

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                unique identifyer for key as UTF-8 string

 //      comm_type (out)         key rating

 //

 //  if an error occurs, *comm_type is set to PEP_ct_unknown and an error

 //  is returned

 DYNAMIC_API PEP_STATUS get_key_rating(

         PEP_SESSION session,

         const char *fpr,

         PEP_comm_type *comm_type

     );

 // renew_key() - renew an expired key

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                ID of key to renew as UTF-8 string

 //      ts (in)                 timestamp when key should expire or NULL for

 //                              default

 DYNAMIC_API PEP_STATUS renew_key(

         PEP_SESSION session,

         const char *fpr,

         const timestamp *ts

     );

 // revoke_key() - revoke a key

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                ID of key to revoke as UTF-8 string

 //      reason (in)             text with reason for revoke as UTF-8 string

 //                              or NULL if reason unknown

 //

 //  caveat:

 //      reason text must not include empty lines

 //      this function is meant for internal use only; better use

 //      key_mistrusted() of keymanagement API

 DYNAMIC_API PEP_STATUS revoke_key(

         PEP_SESSION session,

         const char *fpr,

         const char *reason

     );

 // key_expired() - flags if a key is already expired

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                ID of key to check as UTF-8 string

 //      when (in)               UTC time of when should expiry be considered

 //      expired (out)           flag if key expired

 DYNAMIC_API PEP_STATUS key_expired(

         PEP_SESSION session,

         const char *fpr,

         const time_t when,

         bool *expired

     );

 // key_revoked() - flags if a key is already revoked

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                ID of key to check as UTF-8 string

 //      revoked (out)           flag if key revoked

 DYNAMIC_API PEP_STATUS key_revoked(

         PEP_SESSION session,

         const char *fpr,

         bool *revoked

     );

 PEP_STATUS get_key_userids(

         PEP_SESSION session,

         const char* fpr,

         stringlist_t** keylist

     );

 // get_crashdump_log() - get the last log messages out

 //

 //  parameters:

 //      session (in)            session handle

 //      maxlines (in)           maximum number of lines (0 for default)

 //      logdata (out)           logdata as string in double quoted CSV format

 //                              column1 is title

 //                              column2 is entity

 //                              column3 is description

 //                              column4 is comment

 //

 //  caveat:

 //      the ownership of logdata goes to the caller

 DYNAMIC_API PEP_STATUS get_crashdump_log(

         PEP_SESSION session,

         int maxlines,

         char **logdata

     );

 // get_languagelist() - get the list of languages

 //

 //  parameters:

 //      session (in)            session handle

 //      languages (out)         languages as string in double quoted CSV format

 //                              column 1 is the ISO 639-1 language code

 //                              column 2 is the name of the language

 //

 //  caveat:

 //      the ownership of languages goes to the caller

 DYNAMIC_API PEP_STATUS get_languagelist(

         PEP_SESSION session,

         char **languages

     );

 // get_phrase() - get phrase in a dedicated language through i18n

 //

 //  parameters:

 //      session (in)            session handle

 //      lang (in)               C string with ISO 639-1 language code

 //      phrase_id (in)          id of phrase in i18n

 //      phrase (out)            phrase as UTF-8 string

 //

 //  caveat:

 //      the ownership of phrase goes to the caller

 DYNAMIC_API PEP_STATUS get_phrase(

         PEP_SESSION session,

         const char *lang,

         int phrase_id,

         char **phrase

     );

 // sequence_value() - raise the value of a named sequence and retrieve it

 //

 //  parameters:

 //      session (in)            session handle

 //      name (inout)            name of sequence or char[37] set to {0, }

 //                              for new own sequence named as UUID

 //      value (inout)           value of sequence value to test or 0 for

 //                              getting next value

 //

 //  returns:

 //      PEP_STATUS_OK                   no error, not own sequence

 //      PEP_SEQUENCE_VIOLATED           if sequence violated

 //      PEP_CANNOT_INCREASE_SEQUENCE    if sequence cannot be increased

 //      PEP_OWN_SEQUENCE                if own sequence

 DYNAMIC_API PEP_STATUS sequence_value(

         PEP_SESSION session,

         char *name,

         int32_t *value

     );

 // set_revoked() - records relation between a revoked key and its replacement

 //

 //  parameters:

 //      session (in)            session handle

 //      revoked_fpr (in)        revoked fingerprint

 //      replacement_fpr (in)    replacement key fingerprint

 //      revocation_date (in)    revocation date

 DYNAMIC_API PEP_STATUS set_revoked(

        PEP_SESSION session,

        const char *revoked_fpr,

        const char *replacement_fpr,

        const uint64_t revocation_date

     );

 // get_revoked() - find revoked key that may have been replaced by given key, if any

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                given fingerprint

 //      revoked_fpr (out)       revoked fingerprint

 //      revocation_date (out)   revocation date

 DYNAMIC_API PEP_STATUS get_revoked(

         PEP_SESSION session,

         const char *fpr,

         char **revoked_fpr,

         uint64_t *revocation_date

     );

 // key_created() - get creation date of a key

 //

 //  parameters:

 //      session (in)            session handle

 //      fpr (in)                fingerprint of key

 //      created (out)           date of creation

 PEP_STATUS key_created(

         PEP_SESSION session,

         const char *fpr,

         time_t *created

     );

 // find_private_keys() - find keys in keyring

 //

 //  parameters:

 //      session (in)            session handle

 //      pattern (in)            key id, user id or address to search for as

 //                              UTF-8 string

 //      keylist (out)           list of fingerprints found or NULL on error

 //

 //  caveat:

 //        the ownerships of keylist isgoing to the caller

 //        the caller must use free_stringlist() to free it

 PEP_STATUS find_private_keys(PEP_SESSION session, const char* pattern,

                              stringlist_t **keylist);

 // get_engine_version() - returns the current version of pEpEngine (this is different

 //                        from the pEp protocol version!)

 //

 //  parameters: none

 //

 //  return_value: const char* to the engine version string constant

 //

 DYNAMIC_API const char* get_engine_version();

 // is_pep_user() - returns true if the USER corresponding to this identity 

 //                 has been listed in the *person* table as a pEp user. 

 //

 //  parameters:

 //      identity (in) - identity containing the user_id to check (this is

 //                      the only part of the struct we require to be set)

 //      is_pep (out)  - boolean pointer - will return true or false by

 //                      reference with respect to whether or not user is

 //                      a known pep user

 //

 //  return_value: PEP_STATUS_OK if user found in person table

 //                PEP_ILLEGAL_VALUE if no user_id in input

 //                PEP_CANNOT_FIND_PERSON if user_id doesn't exist

 //

 //  caveat: This *does not check comm_type*

 //                         

 DYNAMIC_API PEP_STATUS is_pep_user(PEP_SESSION session, 

                                    pEp_identity *identity, 

                                    bool* is_pep);

 DYNAMIC_API PEP_STATUS reset_peptest_hack(PEP_SESSION session);

 // This is used internally when there is a temporary identity to be retrieved

 // that may not yet have an FPR attached. See get_identity() for functionality,

 // params and caveats.

 PEP_STATUS get_identity_without_trust_check(

         PEP_SESSION session,

         const char *address,

         const char *user_id,

         pEp_identity **identity

     );

 PEP_STATUS get_identities_by_address(

         PEP_SESSION session,

         const char *address,

         identity_list** id_list

     );

 PEP_STATUS replace_userid(PEP_SESSION session, const char* old_uid,

                               const char* new_uid);

 PEP_STATUS remove_fpr_as_default(PEP_SESSION session, 

                                     const char* fpr);

 PEP_STATUS get_main_user_fpr(PEP_SESSION session, 

                              const char* user_id,

                              char** main_fpr);

 PEP_STATUS replace_main_user_fpr(PEP_SESSION session, const char* user_id,

                               const char* new_fpr);

 PEP_STATUS refresh_userid_default_key(PEP_SESSION session, const char* user_id);

 // This ONLY sets the *user* flag, and creates a shell identity if necessary.

 PEP_STATUS set_as_pep_user(PEP_SESSION session, pEp_identity* user);

 // returns true (by reference) if a person with this user_id exists; 

 // Also replaces aliased user_ids by defaults in identity.

 PEP_STATUS exists_person(PEP_SESSION session, pEp_identity* identity, bool* exists);

 PEP_STATUS set_pgp_keypair(PEP_SESSION session, const char* fpr);

 #ifdef __cplusplus

 }

 #endif