wtls.c

WTLS安全层源程序

                      return "unknown state";
       }
}


/*
 * Feed an event to a WTP responder state machine. Handle all errors yourself,
 * do not report them to the caller. Note: Do not put {}s of the else block 
 * inside the macro definition. 
 */
static void wtls_event_handle(WTLSMachine *wtls_machine, WAPEvent *event){

     debug("wap.wtls", 0, "WTLS: wtls_machine %ld, state %s, event %s.", 
	   wtls_machine->mid, 
	   name_wtls_state(wtls_machine->state), 
	   wap_event_name(event->type));

	/* for T_Unitdata_Ind PDUs */
	if(event->type == T_Unitdata_Ind) {
		/* if encryption: decrypt all pdus in the list */
		if( wtls_machine->encrypted ) {
			wtls_decrypt_pdu_list(wtls_machine, event->u.T_Unitdata_Ind.pdu_list);
		}
		/* add all handshake data to wtls_machine->handshake_data */
		//add_all_handshake_data(wtls_machine, event->u.T_Unitdata_Ind.pdu_list);

	}
	
     #define STATE_NAME(state)
     #define ROW(wtls_state, event_type, condition, action, next_state) \
	     if (wtls_machine->state == wtls_state && \
		event->type == event_type && \
		(condition)) { \
		action \
		wtls_machine->state = next_state; \
		debug("wap.wtls", 0, "WTLS %ld: New state %s", wtls_machine->mid, #next_state); \
	     } else 
     #include "wtls_state-decl.h"
	     {
		error(0, "WTLS: handle_event: unhandled event!");
		debug("wap.wtls", 0, "WTLS: handle_event: Unhandled event was:");
		wap_event_destroy(event);
		return;
	     }

     if (event != NULL) {
	wap_event_destroy(event);  
     }

     if (wtls_machine->state == NULL_STATE)
     	wtls_machine_destroy(wtls_machine);
}

/*
 * Checks whether wtls machines data structure includes a specific machine.
 * The machine in question is identified with with source and destination
 * address and port.
 */

static WTLSMachine *wtls_machine_find_or_create(WAPEvent *event) {

          WTLSMachine *wtls_machine = NULL;
          long mid;
          WAPAddrTuple *tuple;

          tuple = NULL;
          mid = -1;

		  debug("wap.wtls",0, "event->type = %d", event->type);
		  
          /* Get the address that this PDU came in from */
          switch (event->type) {
          case T_Unitdata_Ind:
          case T_DUnitdata_Ind:
                  tuple = event->u.T_Unitdata_Ind.addr_tuple;
                  break;
          case SEC_Create_Request_Req:
          case SEC_Terminate_Req:
          case SEC_Exception_Req:
          case SEC_Create_Res:
          case SEC_Exchange_Req:
          case SEC_Commit_Req:
          case SEC_Unitdata_Req:
                  tuple = event->u.T_Unitdata_Ind.addr_tuple;
                  break;
          default:
                  debug("wap.wtls", 0, "WTLS: wtls_machine_find_or_create:"
                        "unhandled event (1)"); 
                  wap_event_dump(event);
                  return NULL;
          }

          /* Either the address or the machine id must be available at this point */
          gw_assert(tuple != NULL || mid != -1);

          /* Look for the machine owning this address */
          wtls_machine = wtls_machine_find(tuple, mid);

          /* Oh well, we didn't find one. We'll create one instead, provided
             it meets certain criteria */
          if (wtls_machine == NULL){
                  switch (event->type){
                  case SEC_Create_Request_Req:
                          /* State NULL, case 1 */
                          debug("wap.wtls",0,"WTLS: received a SEC_Create_Request_Req, and don't know what to do with it...");
                          /* Create and dispatch a T_Unitdata_Req containing a HelloRequest */
                          /* And there's no need to do anything else, 'cause we return to state NULL */
                          break;
                  case T_Unitdata_Ind:
                  case T_DUnitdata_Ind:
                          /* State NULL, case 3 */
/*                           if (wtls_event_type(event) == Alert_No_Renegotiation) { */
                                  /* Create and dispatch a SEC_Exception_Ind event */
/*                                   debug("wap.wtls",0,"WTLS: received an Alert_no_Renegotiation; just dropped it."); */
                                  /* And there's no need to do anything else, 'cause we return to state NULL */
/*                                   break; */
/*                           } else */
/*                           if (event->u.T_Unitdata_Ind == ClientHello) { */
                                  /* State NULL, case 2 */
                          wtls_machine = wtls_machine_create(tuple);
                          /* And stick said event into machine, which should push us into state
                             CREATING after a SEC_Create_Ind */
/*                           } */
                          break;
                  default:
                          error(0, "WTLS: wtls_machine_find_or_create:"
                                " unhandled event (2)");
                          wap_event_dump(event);
                          break;
                  }
          }
          return wtls_machine;
}

static int is_wanted_wtls_machine(void *a, void *b) {
	machine_pattern *pat;
	WTLSMachine *m;
	
	m = a;
	pat = b;

	if (m->mid == pat->mid)
		return 1;

	if (pat->mid != -1)
		return 0;

	return wap_addr_tuple_same(m->addr_tuple, pat->tuple);
}


static WTLSMachine *wtls_machine_find(WAPAddrTuple *tuple, 
                                         long mid) {
	machine_pattern pat;
	WTLSMachine *m;
	
	pat.tuple = tuple;
	pat.mid = mid;
	
	m = list_search(wtls_machines, &pat, is_wanted_wtls_machine);
	return m;
}


static WTLSMachine *wtls_machine_create(WAPAddrTuple *tuple) {

        WTLSMachine *wtls_machine;
        wtls_machine = gw_malloc(sizeof(WTLSMachine)); 
        
        #define MACHINE(field) field
        #define ENUM(name) wtls_machine->name = NULL_STATE;
        #define ADDRTUPLE(name) wtls_machine->name = NULL; 
        #define INTEGER(name) wtls_machine->name = 0; 
        #define OCTSTR(name) wtls_machine->name = NULL;
        #define PDULIST(name) wtls_machine->name = NULL;
        #include "wtls_machine-decl.h"
        
        list_append(wtls_machines, wtls_machine);
        wtls_machine->mid = counter_increase(wtls_machine_id_counter);
        wtls_machine->addr_tuple = wap_addr_tuple_duplicate(tuple);

		wtls_machine->handshake_data = octstr_create("");
		
        debug("wap.wtls", 0, "WTLS: Created WTLSMachine %p (%ld)",
              (void *) wtls_machine, wtls_machine->mid);
        return wtls_machine;
}

/*
 * Destroys a WTLSMachine. Assumes it is safe to do so. Assumes it has 
 * already been deleted from the machines list.
 */
static void wtls_machine_destroy(void * p) {
       WTLSMachine *wtls_machine;

       wtls_machine = p;
       debug("wap.wtls", 0, "WTLS: Destroying WTLSMachine %p (%ld)",
             (void *) wtls_machine, wtls_machine->mid);
       list_delete_equal(wtls_machines, wtls_machine);        
        
       #define MACHINE(field) field
       #define ENUM(name) wtls_machine->name = NULL_STATE;
       #define ADDRTUPLE(name) wap_addr_tuple_destroy(wtls_machine->name); 
       #define INTEGER(name) wtls_machine->name = 0; 
       #define OCTSTR(name) octstr_destroy(wtls_machine->name);
       #define PDULIST(name) wtls_machine->name = NULL;
       #include "wtls_machine-decl.h"

        gw_free(wtls_machine);
}


/*
 * Create a TR-Invoke.ind event.
static WAPEvent *create_tr_invoke_ind(WTPRespMachine *sm, Octstr *user_data) {
	WAPEvent *event;
	
	event = wap_event_create(TR_Invoke_Ind);
	event->u.TR_Invoke_Ind.ack_type = sm->u_ack;
	event->u.TR_Invoke_Ind.user_data = octstr_duplicate(user_data);
	event->u.TR_Invoke_Ind.tcl = sm->tcl;
	event->u.TR_Invoke_Ind.addr_tuple = 
		wap_addr_tuple_duplicate(sm->addr_tuple);
	event->u.TR_Invoke_Ind.handle = sm->mid;
	return event;
}
*/

/*
 * Create a TR-Result.cnf event.
static WAPEvent *create_tr_result_cnf(WTPRespMachine *sm) {
	WAPEvent *event;
	
	event = wap_event_create(TR_Result_Cnf);
	event->u.TR_Result_Cnf.addr_tuple = 
		wap_addr_tuple_duplicate(sm->addr_tuple);
	event->u.TR_Result_Cnf.handle = sm->mid;
	return event;
}
*/

/*
 * Creates TR-Abort.ind event from a responder state machine. 
 
static WAPEvent *create_tr_abort_ind(WTPRespMachine *sm, long abort_reason) {
	WAPEvent *event;
	
	event = wap_event_create(TR_Abort_Ind);

	event->u.TR_Abort_Ind.abort_code = abort_reason;
	event->u.TR_Abort_Ind.addr_tuple = 
		wap_addr_tuple_duplicate(sm->addr_tuple);
	event->u.TR_Abort_Ind.handle = sm->mid;

	return event;
}
*/

static int wtls_machine_has_mid(void *a, void *b) {
	WTLSMachine *sm;
	long mid;
	
	sm = a;
	mid = *(long *) b;
	return sm->mid == mid;
}

static WTLSMachine *find_wtls_machine_using_mid(long mid) {
       return list_search(wtls_machines, &mid, wtls_machine_has_mid);
}

/* Used for list searches */
static int match_handshake_type(void* item, void* pattern)
{
        wtls_Payload* matchingPayload;
        int type;
        int retrievedType;
        
        matchingPayload = (wtls_Payload*) item;
        type = (int) pattern;
        
        retrievedType = octstr_get_char(matchingPayload->data, 0);
        
        if (matchingPayload->type == Handshake_PDU && retrievedType == type)
        {
                return 1;
        }
        else
        {
                return 0;
        }        
}

static int match_pdu_type(void* item, void* pattern)
{
        wtls_Payload* matchingPayload;
        int type;
        
        matchingPayload = (wtls_Payload*) item;
        type = (int) pattern;
        
        
        if (matchingPayload->type == type)
        {
                return 1;
        }
        else
        {
                return 0;
        }        
}

#endif