C++ (Cpp) _mem_sum_ip Examples

Example #1

File: alggen.c Project: kylemanna/kinetis-sdk1

void NAT_ALG_TCP_checksum
   (
      IP_HEADER_PTR    ip_header_ptr    /* [IN]  pointer to IP header */
   )
{ /* Body */
   TRANSPORT_UNION    transport;
   uint16_t           checksum;
   uint16_t           protocol;
   uint16_t           iplen = IPH_LEN(ip_header_ptr);
   uint16_t           len = mqx_ntohs(ip_header_ptr->LENGTH) - iplen; 
   
   /* Get TCP header */
   transport.PTR = TRANSPORT_PTR(ip_header_ptr);

   mqx_htons(transport.TCP_PTR->checksum, 0);    /* Clear checksum field */
   protocol = mqx_ntohc(ip_header_ptr->PROTOCOL); /* PROTOCOL */
   checksum = (uint16_t) _mem_sum_ip(protocol, 8, ip_header_ptr->SOURCE);  /* IP SRC and DST ADDR */
   checksum = (uint16_t) _mem_sum_ip(checksum, len, transport.PTR);

   /* TCP LENGTH */
   checksum = IP_Sum_immediate(checksum, len);
   
   checksum = IP_Sum_invert(checksum);
   mqx_htons(transport.TCP_PTR->checksum, checksum);   

} /* Endbody */

Example #2

File: igmp.c Project: Wangwenxue/FutureMove-T-box

bool IGMP_send_report
   (
      ip_mreq  *igrp,
      uint16_t  type
   )
{ /* Body */
   IGMP_CFG_STRUCT_PTR  IGMP_cfg_ptr = RTCS_getcfg(IGMP);
   uint32_t              error;
   uint16_t              checksum;
   RTCSPCB_PTR          pcb;
   IGMP_HEADER_PTR      header;
   IP_IF_PTR            ipif;
   _ip_address          ipdst;

   IF_IGMP_STATS_ENABLED(IGMP_cfg_ptr->STATS.COMMON.ST_TX_TOTAL++);

   /* never send a report for the local groups */
   if (IN_LOCAL_MULTICAST(igrp->imr_multiaddr.s_addr)) {
      return TRUE;
   } /* Endif */

   /* get the interface with its ip address */
   ipif = IP_find_if(igrp->imr_interface.s_addr);
   if (ipif == NULL) {
      IF_IGMP_STATS_ENABLED(IGMP_cfg_ptr->STATS.COMMON.ST_TX_MISSED++);
      return FALSE;
   } /* Endif */

   pcb = RTCSPCB_alloc_send();
   if (pcb == NULL) {
      IF_IGMP_STATS_ENABLED(IGMP_cfg_ptr->STATS.COMMON.ST_TX_MISSED++);
      return FALSE;
   } /* Endif */

   //RTCSLOG_PCB_ALLOC(pcb);

   error = RTCSPCB_insert_header(pcb, sizeof(IGMP_HEADER));
   if (error) {
      RTCSLOG_PCB_FREE(pcb, error);
      RTCSPCB_free(pcb);
      IF_IGMP_STATS_ENABLED(IGMP_cfg_ptr->STATS.COMMON.ST_TX_MISSED++);
      return FALSE;
   } /* Endif */

   RTCSLOG_PCB_WRITE(pcb, RTCS_LOGCTRL_PROTO(IPPROTO_IGMP), 1);

#ifdef IGMP_V2
   /* check if routers igmpv1 are present or not */
   if (type == IGMPTYPE_V2_REPORT && ipif->IGMP_V1_ROUTER_FLAG) {
      uint32_t curTime = RTCS_time_get();
      /* WORK: handle the overflow (see tcp seq) */
      if (curTime < ipif->IGMP_V1_ROUTER_TIMEOUT) {
         type = IGMPTYPE_V1_REPORT;
      } else {
         /* if the timeout expired, clear the flag */
         ipif->IGMP_V1_ROUTER_FLAG = 0;
      } /* Endif */
   } /* Endif */
#endif   /* IGMP_V2 */

   /* build the igmp packet */
   header = (IGMP_HEADER_PTR)RTCSPCB_DATA(pcb);
   mqx_htonc(header->TYPE, type);
   mqx_htonc(header->MAX_RESP_TIME, 0);
   mqx_htons(header->CHECKSUM, 0);
   mqx_htonl(header->GROUP_ADDRESS, igrp->imr_multiaddr.s_addr);
   checksum = _mem_sum_ip(0, sizeof(IGMP_HEADER), header);
   checksum = IP_Sum_invert(checksum);
   mqx_htons(header->CHECKSUM, checksum);

   /* WORK: for IGMP_V2, add a router alert option but currently ip layer doesnt support ip options */

   /* send the igmp packet */
   ipdst = igrp->imr_multiaddr.s_addr;
#ifdef IGMP_V2
   if (type == IGMPTYPE_LEAVE) {
      ipdst = INADDR_ALLROUTERS_GROUP;
   } /* Endif */
#endif

   IF_IGMP_STATS_ENABLED(IGMP_cfg_ptr->STATS.ST_TX_REPORT++);    /* WORK: not always true for IGMP_V2 */
   error = IP_send(pcb, IPPROTO_IGMP | IPTTL(1), igrp->imr_interface.s_addr, ipdst, RTCS_MSG_NOLOOP);

   return TRUE;
} /* Endbody */