// --------------------------------------------------------------------------
// _do_send: Private function used to send an ICMP ECHO REQUEST.
// Creates an ICMP ECHO REQUEST packet and sends it. Creates an echo event
// and inserts it in the engine's list of echo events.
//
// Parameters:
// p_engine: Pointer to a ICMP_ECHO_ENGINE_PARMS structure.
//
// Return values:
// IEE_SUCCESS when no errors happened.
// IEE_GENERAL_ECHO_ERROR on fatal error.
//
iee_priv_ret_t _do_send( PICMP_ECHO_ENGINE_PARMS p_engine )
{
PICMP_ECHO_HEADER icmp_hdr;
uint8_t send_buf[sizeof(ICMP_ECHO_HEADER) + ICMP_ECHO_DATA_LEN];
const uint16_t send_buf_len = sizeof(ICMP_ECHO_HEADER) + ICMP_ECHO_DATA_LEN;
iee_priv_ret_t retval = SEND_PINGOUT_SUCCESS;
sint32_t ret;
// Map the ICMP header unto the send buffer.
icmp_hdr = (PICMP_ECHO_HEADER)send_buf;
if( p_engine->icmp_saf == AF_INET )
{
icmp_hdr->icmp_type = ICMP4_ECHO_REQUEST_TYPE;
}
else
{
icmp_hdr->icmp_type = ICMP6_ECHO_REQUEST_TYPE;
}
icmp_hdr->icmp_code = ICMP_ECHO_CODE;
icmp_hdr->icmp_cksm = 0;
icmp_hdr->echo_id = p_engine->icmp_echo_id;
icmp_hdr->echo_seq = (p_engine->count_send)++; // Starts at 0.
pal_gettimeofday( (struct timeval*)(icmp_hdr->echo_data) );
// Calculate the ICMP header checksum.
_calc_icmp_csum( p_engine, icmp_hdr );
// Create the echo event, and insert it in the echo engine sorted echo
// event list.
if( _create_insert_echo_event( p_engine,
(struct timeval*)(icmp_hdr->echo_data), icmp_hdr->echo_seq ) != NULL )
{
// Send the ICMP packet.
DBG_PRINT(">> %s ECHO REQUEST, id:%d, seq:%d, len:%d...\n",
ICMP_LITTERAL, icmp_hdr->echo_id, icmp_hdr->echo_seq, send_buf_len );
ret = sendto( p_engine->icmp_sfd, send_buf, send_buf_len, 0, (struct sockaddr*)&(p_engine->echo_addr_dst), sizeof(p_engine->echo_addr_dst) );
if( ret != send_buf_len )
{
// The return value of 'sendto()' did not match what was expected. Error.
retval = SEND_PINGOUT_ERROR;
DBG_PRINT("Failed to send ICMP REQUEST packet. Error code:%d\n", ret);
}
else if( p_engine->clbk_send != NULL )
{
p_engine->clbk_send();
}
}
else
{
// Resource starvation. Not enough memory.
retval = SEND_MEMORY_STARVATION;
DBG_PRINT("Failed to allocate memory for echo event.\n");
}
return retval;
}
/*
* Generate a DNS id
*/
static uint16_t
DNSGenerateID(void)
{
static uint16_t id = 0;
struct timeval now;
pal_gettimeofday(&now);
if (!id)
id = (uint16_t) (0xffff & (now.tv_sec ^ now.tv_usec ^ pal_getpid()));
else
id += 1 + (uint16_t)(now.tv_usec % 263);
return id;
}
// --------------------------------------------------------------------------
// IEE_process: ICMP Echo Engine main processing routine.
//
// Parameters:
// p_config: Opaque pointer to a ICMP_ECHO_ENGINE_PARMS structure.
//
// Return values:
// IEE_SUCCESS on normal execution.
// IEE_INVALID_PARMS if invalid p_config.
// IEE_CONNECTIVITY_ASSESSED (ACD only) Received one echo reply on time.
// IEE_GENERAL_ECHO_TIMEOUT when the maximal number of successive timeouts
// has been detected.
// IEE_GENERAL_ECHO_ERROR on a fatal error.
//
iee_ret_t IEE_process( void* p_config )
{
PICMP_ECHO_ENGINE_PARMS p_engine = (PICMP_ECHO_ENGINE_PARMS)p_config;
struct timeval tv_reference;
iee_ret_t retval = IEE_SUCCESS;
// Verify input parameters.
if( p_engine == NULL )
{
// Error: invalid p_config, or already freed.
return IEE_INVALID_PARMS;
}
if( (iee_mode_t)p_engine->eng_mode == IEE_MODE_KA )
{
// When icmp echo engine is is Keepalive(KA) mode, the first sent echo
// REQUEST is sent after a full interval. => Wait for one interval.
uint32_t total_sleep_time = p_engine->send_interval;
uint32_t sleep_time;
DBG_PRINT("Sleeping %d milliseconds before sending first ECHO REQUEST.\n", total_sleep_time);
// Break the sleep in several chunks in case we're notified to stop.
while( p_engine->eng_ongoing == 1 && total_sleep_time > 0 )
{
sleep_time = (total_sleep_time>1000)?1000:total_sleep_time;
pal_sleep( sleep_time );
total_sleep_time -= sleep_time;
}
}
// ------------------------------------------------------------------------
// Main ICMP echo engine loop. Loop until we're notified to stop, or we've
// sent the number of ECHO REQUESTS we had to.
// ------------------------------------------------------------------------
while( p_engine->eng_ongoing == 1 &&
(p_engine->echo_num == 0 || p_engine->count_send < p_engine->echo_num) )
{
// ------------------------------
// Time to send an ECHO request.
// ------------------------------
retval = _do_send_wrap( p_engine );
if( retval != IEE_SUCCESS )
{
// An error occurred while sending.
break;
}
// Check if we've been notified to stop, or an event has triggered a stop.
if( p_engine->eng_ongoing == 0 )
{
// Stop processing.
break;
}
// Synchronize time reference variable with 'now'.
pal_gettimeofday( &tv_reference );
// Add one echo interval to tv_reference.
_compute_next_send( p_engine, &tv_reference );
// -------------------------------------------------------------------
// Wait and read for incoming packets.
// Function will return when tv_reference is approximatively 'now'.
// -------------------------------------------------------------------
retval = _do_read_wrap( p_engine, &tv_reference );
if( retval != IEE_SUCCESS )
{
// A retval different than IEE_SUCCESS indicates that we should stop
// processing. It does not necessarily mean an error occurred.
break;
}
DBG_PRINT("\n");
}
DBG_PRINT("Statistics:\n\tSent: %03d\n\tReceived on time: %03d\n\tReceived late: %03d\n",
p_engine->count_send, p_engine->count_ontime, p_engine->count_late );
return retval;
}
