// This file is under GNU General Public License 3.0

 // see LICENSE.txt

 #include "pEp_internal.h"

 #include "dynamic_api.h"

 #include "message_api.h"

 #include <string.h>

 #include <stdlib.h>

 PEP_STATUS has_key_reset_been_sent(

         PEP_SESSION session, 

         const char* user_id, 

         const char* revoked_fpr,

         bool* contacted)

 {

     assert(session);

     assert(contacted);

     assert(user_id);

     assert(revoked_fpr);

     assert(!EMPTYSTR(user_id));

     if (!session || !contacted || EMPTYSTR(revoked_fpr) || EMPTYSTR(user_id))

         return PEP_ILLEGAL_VALUE;

     *contacted = false;

     char* alias_default = NULL;

     PEP_STATUS status = get_userid_alias_default(session, user_id, &alias_default);

     if (status == PEP_CANNOT_FIND_ALIAS || EMPTYSTR(alias_default)) {

         free(alias_default);

         alias_default = strdup(user_id);

     }

     sqlite3_reset(session->was_id_for_revoke_contacted);

     sqlite3_bind_text(session->was_id_for_revoke_contacted, 1, revoked_fpr, -1,

             SQLITE_STATIC);

     sqlite3_bind_text(session->was_id_for_revoke_contacted, 2, user_id, -1,

             SQLITE_STATIC);        

     int result = sqlite3_step(session->was_id_for_revoke_contacted);

     switch (result) {

         case SQLITE_ROW: {

             *contacted = (sqlite3_column_int(session->was_id_for_revoke_contacted, 0) != 0);

             break;

         }

         default:

             sqlite3_reset(session->was_id_for_revoke_contacted);

             free(alias_default);

             return PEP_UNKNOWN_DB_ERROR;

     }

     sqlite3_reset(session->was_id_for_revoke_contacted);

     return PEP_STATUS_OK;

 }

 //static const char *sql_set_revoke_contact_as_notified =

 //    "insert or replace into revocation_contact_list(fpr, contact_id) values (?1, ?2) ;";

 PEP_STATUS set_reset_contact_notified(

         PEP_SESSION session,

         const char* revoke_fpr,

         const char* contact_id

     )

 {

     PEP_STATUS status = PEP_STATUS_OK;

     assert(session && !EMPTYSTR(revoke_fpr) && !EMPTYSTR(contact_id));

     if (!session || EMPTYSTR(revoke_fpr) || EMPTYSTR(contact_id))

         return PEP_ILLEGAL_VALUE;

     sqlite3_reset(session->set_revoke_contact_as_notified);

     sqlite3_bind_text(session->set_revoke_contact_as_notified, 1, revoke_fpr, -1, 

             SQLITE_STATIC);

     sqlite3_bind_text(session->set_revoke_contact_as_notified, 2, contact_id, -1,

             SQLITE_STATIC);

     int result;

     result = sqlite3_step(session->set_revoke_contact_as_notified);

     switch (result) {

         case SQLITE_DONE:

             status = PEP_STATUS_OK;

             break;

         default:

             status = PEP_UNKNOWN_DB_ERROR;

     }

     sqlite3_reset(session->set_revoke_contact_as_notified);

     return status;    

 }

 PEP_STATUS receive_key_reset(PEP_SESSION session,

                              message* reset_msg) {

     if (!session || !reset_msg)

         return PEP_ILLEGAL_VALUE;

     pEp_identity* sender_id = reset_msg->from;

     if (!sender_id)

         return PEP_MALFORMED_KEY_RESET_MSG;

     PEP_STATUS status = update_identity(session, sender_id);

     if (!sender_id->user_id)

         return PEP_UNKNOWN_ERROR;

     if (is_me(session, sender_id))

         return PEP_ILLEGAL_VALUE;    

     if (!reset_msg->longmsg || strncmp(reset_msg->longmsg, "OLD: ", 5) != 0) 

         return PEP_MALFORMED_KEY_RESET_MSG;

     status = PEP_STATUS_OK;

     char* old_fpr = NULL;

     char* new_fpr = NULL;

     stringlist_t* keylist = NULL;

     pEp_identity* temp_ident = identity_dup(sender_id);

     if (!temp_ident) {

         status = PEP_OUT_OF_MEMORY;

         goto pEp_free;

     }        

     char* rest = NULL;

     char* p = strtok_r(reset_msg->longmsg, "\r\n", &rest);

     if (!EMPTYSTR(p + 5))

         old_fpr = strdup(p + 5);

     else {

         status = PEP_MALFORMED_KEY_RESET_MSG;

         goto pEp_free;

     }

     bool own_key = false;

     status = is_own_key(session, old_fpr, &own_key);

     if (own_key) {

         // Nope, no one can make us our own default. If we want to do that,

         // that's keysync, NOT key reset.

         status = PEP_ILLEGAL_VALUE;

         goto pEp_free;

     }

     p = strtok_r(NULL, "\r\n", &rest); 

     if (strncmp(p, "NEW: ", 5) != 0  || EMPTYSTR(p + 5)) {

         status = PEP_MALFORMED_KEY_RESET_MSG;

         goto pEp_free;

     }

     new_fpr = strdup(p + 5);

     // Reset the original key

     status = key_reset(session, old_fpr, temp_ident);

     if (status != PEP_STATUS_OK)

         goto pEp_free;

     status = find_keys(session, new_fpr, &keylist);

     if (status != PEP_STATUS_OK)

         goto pEp_free;

     if (!keylist) {

         status = PEP_KEY_NOT_FOUND;

         goto pEp_free;

     }

     // alright, we've checked as best we can. Let's set that baby.

     sender_id->fpr = new_fpr;

     // This only sets as the default, does NOT TRUST IN ANY WAY

     sender_id->comm_type = sender_id->comm_type & (~PEP_ct_confirmed);

     status = set_identity(session, sender_id);

     sender_id->fpr = NULL; // ownership for free

 pEp_free:    

     free_stringlist(keylist);    

     free(old_fpr);

     free(new_fpr);

     free_identity(temp_ident);

     return status;

 }

 PEP_STATUS create_standalone_key_reset_message(PEP_SESSION session,

                                                message** dst, 

                                                pEp_identity* recip,

                                                const char* old_fpr,

                                                const char* new_fpr) {

     if (!dst || !recip->user_id || !recip->address)

         return PEP_ILLEGAL_VALUE;

     if (!old_fpr || !new_fpr)

         return PEP_ILLEGAL_VALUE;

     *dst = NULL;

     // Get own identity user has corresponded with

     pEp_identity* own_identity = NULL;

     PEP_STATUS status = get_own_ident_for_contact_id(session,

                                                      recip,

                                                      &own_identity);                                                       

     if (status != PEP_STATUS_OK)

         return status;

     message* reset_message = new_message(PEP_dir_outgoing);

     reset_message->from = own_identity;

     reset_message->to = new_identity_list(identity_dup(recip)); // ?

     const char* oldtag = "OLD: ";

     const char* newtag = "\nNEW: ";

     const size_t taglens = 11;

     size_t full_len = taglens + strlen(old_fpr) + strlen(new_fpr) + 2; // \n and \0

     char* longmsg = calloc(full_len, 1);

     strlcpy(longmsg, oldtag, full_len);

     strlcat(longmsg, old_fpr, full_len);

     strlcat(longmsg, newtag, full_len);

     strlcat(longmsg, new_fpr, full_len);

     strlcat(longmsg, "\n", full_len);

     reset_message->longmsg = longmsg; 

     reset_message->shortmsg = strdup("Key reset");    

     message* output_msg = NULL;

     status = encrypt_message(session, reset_message, NULL,

                              &output_msg, PEP_enc_PGP_MIME,

                              PEP_encrypt_flag_key_reset_only);

     if (status == PEP_STATUS_OK)

         *dst = output_msg;

     free_message(reset_message);

     return status;

 }

 PEP_STATUS send_key_reset_to_recents(PEP_SESSION session,

                                      const char* old_fpr, 

                                      const char* new_fpr) {

     assert(old_fpr);

     assert(new_fpr);

     assert(session);

     assert(session->messageToSend);

     if (!session || !old_fpr || !new_fpr)

         return PEP_ILLEGAL_VALUE;

     messageToSend_t send_cb = session->messageToSend;

     if (!send_cb)

         return PEP_SYNC_NO_MESSAGE_SEND_CALLBACK;

     identity_list* recent_contacts = NULL;

     message* reset_msg = NULL;

     PEP_STATUS status = get_last_contacted(session, &recent_contacts);

     if (status != PEP_STATUS_OK)

         goto pEp_free;

     identity_list* curr_id_ptr = recent_contacts;

     for (curr_id_ptr = recent_contacts; curr_id_ptr; curr_id_ptr = curr_id_ptr->next) {

         pEp_identity* curr_id = curr_id_ptr->ident;

         if (!curr_id)

             break;

         const char* user_id = curr_id->user_id;

         // Should be impossible, but?

         if (!user_id)

             continue;

         // Check if it's us - if so, pointless...

         if (is_me(session, curr_id))

             continue;

         // Check if they've already been told - this shouldn't be the case, but...

         bool contacted = false;

         status = has_key_reset_been_sent(session, user_id, old_fpr, &contacted);

         if (status != PEP_STATUS_OK)

             goto pEp_free;

         if (contacted)

             continue;

         // if not, make em a message    

         reset_msg = NULL;

         status = create_standalone_key_reset_message(session,

                                                      &reset_msg,

                                                      curr_id,

                                                      old_fpr,

                                                      new_fpr);

         if (status == PEP_CANNOT_FIND_IDENTITY) { // this is ok, just means we never mailed them 

             status = PEP_STATUS_OK;

             continue; 

         }

         if (status != PEP_STATUS_OK) {

             free(reset_msg);

             goto pEp_free;

         }

         // insert into queue

         status = send_cb(reset_msg);

         if (status != PEP_STATUS_OK) {

             free(reset_msg);

             goto pEp_free;            

         }

         // Put into notified DB

         status = set_reset_contact_notified(session, old_fpr, user_id);

         if (status != PEP_STATUS_OK)

             goto pEp_free;            

     }

 pEp_free:

     free_identity_list(recent_contacts);

     return status;

 }

 DYNAMIC_API PEP_STATUS key_reset(

         PEP_SESSION session,

         const char* key_id,

         pEp_identity* ident

     )

 {

     if (!session)

         return PEP_ILLEGAL_VALUE;

     PEP_STATUS status = PEP_STATUS_OK;

     char* fpr_copy = NULL;

     char* own_id = NULL;

     char* new_key = NULL;

     identity_list* key_idents = NULL;

     stringlist_t* keys = NULL;

     if (!EMPTYSTR(key_id)) {

         fpr_copy = strdup(key_id);

         if (!fpr_copy)

             return PEP_OUT_OF_MEMORY;

     }

     if (!ident) {

         // Get list of own identities

         status = get_default_own_userid(session, &own_id);

         if (status != PEP_STATUS_OK)

             goto pEp_free;

         if (EMPTYSTR(fpr_copy)) {

             status = get_all_keys_for_user(session, own_id, &keys);

             if (status == PEP_STATUS_OK) {

                 stringlist_t* curr_key;

                 for (curr_key = keys; curr_key && curr_key->value; curr_key = curr_key->next) {

                     status = key_reset(session, curr_key->value, NULL);

                     if (status != PEP_STATUS_OK)

                         break;

                 }

             }

             goto pEp_free;

         } // otherwise, we have a specific fpr to process

         // fpr_copy exists, so... let's go.

         // Process own identities with this fpr

         status = get_identities_by_main_key_id(session, fpr_copy, &key_idents);

         if (status == PEP_STATUS_OK) {

             // have ident list, or should

             identity_list* curr_ident;

             for (curr_ident = key_idents; curr_ident && curr_ident->ident; 

                  curr_ident = curr_ident->next) {

                 pEp_identity* this_identity = curr_ident->ident;

                 status = key_reset(session, fpr_copy, this_identity);

                 if (status != PEP_STATUS_OK)

                     break;                    

             }

         }

         else if (status == PEP_CANNOT_FIND_IDENTITY) // not an error

             status = PEP_STATUS_OK;

         goto pEp_free;

     }

     else { // an identity was specified.       

         if (is_me(session, ident)) {            

             // FIXME: make sure this IS our fpr?

             // If it got sent in with an empty fpr...

             if (EMPTYSTR(fpr_copy)) {

                 //

                 // if (!EMPTYSTR(ident->fpr))

                 //     fpr_copy = strdup(ident->fpr);

                 status = _myself(session, ident, false, true, true);

                 if (status == PEP_STATUS_OK && ident->fpr)

                     fpr_copy = strdup(ident->fpr);

                 else {

                     // last resort?

                     // Get list of own identities

                     char* own_id = NULL;

                     status = get_default_own_userid(session, &own_id);

                     if (status == PEP_STATUS_OK)

                         status = get_user_default_key(session, own_id, &fpr_copy);

                     if (status != PEP_STATUS_OK || EMPTYSTR(fpr_copy))  {

                         free(own_id);

                         return (status == PEP_STATUS_OK ? PEP_KEY_NOT_FOUND : status);

                     }

                 }

             }

             free(ident->fpr);

             ident->fpr = fpr_copy;            

             // Create revocation

             status = revoke_key(session, fpr_copy, NULL);

             // generate new key

             if (status == PEP_STATUS_OK) {

                 ident->fpr = NULL;

                 status = generate_keypair(session, ident);

             }

             if (status == PEP_STATUS_OK) {

                 new_key = strdup(ident->fpr);

                 status = set_own_key(session, ident, new_key);

             }

             // mistrust fpr from trust

             ident->fpr = fpr_copy;

             ident->comm_type = PEP_ct_mistrusted;

             status = set_trust(session, ident);

             ident->fpr = NULL;

             // Done with old use of ident.

             if (status == PEP_STATUS_OK) {

                 // Update fpr for outgoing

                 status = myself(session, ident);

             }

             if (status == PEP_STATUS_OK)

                 // cascade that mistrust for anyone using this key

                 status = mark_as_compromised(session, fpr_copy);

             if (status == PEP_STATUS_OK)

                 status = remove_fpr_as_default(session, fpr_copy);

             if (status == PEP_STATUS_OK)

                 status = add_mistrusted_key(session, fpr_copy);

             // add to revocation list 

             if (status == PEP_STATUS_OK) 

                 status = set_revoked(session, fpr_copy, new_key, time(NULL));            

             // for all active communication partners:

             //      active_send revocation

             if (status == PEP_STATUS_OK)

                 status = send_key_reset_to_recents(session, fpr_copy, new_key);

         }

         else { // not is_me

             // TODO: Decide what this means. We have a non-own identity, we don't

             //       have an fpr. Do we reset all keys for that identity?

             if (EMPTYSTR(fpr_copy)) {

                 NOT_IMPLEMENTED

             }

             // remove fpr from all identities

             // remove fpr from all users

             if (status == PEP_STATUS_OK)

                 status = remove_fpr_as_default(session, fpr_copy);

             // delete key from DB

             if (status == PEP_STATUS_OK) {

                 status = remove_key(session, fpr_copy);

             };

         }

     }

 pEp_free:

     free(fpr_copy);

     free(own_id);

     free_identity_list(key_idents);

     free_stringlist(keys);

     free(new_key);    

     return status;

 }