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#include "udp.h"
#include "inet.h"
#include "net_sys.h"
#include "ntp.h"
uint32_t ntp_generic(struct netdev *dev, uint32_t ip, uint16_t src, uint16_t dst, uint8_t* pos,uint8_t *end)
{
pos-=48; // we need 48 bytes
struct udp_v4_ntp *ntp=pos;
ntp->li_vn_mode=0x1b; // Eight bits. li, vn, and mode.
// li. Two bits. Leap indicator.
// vn. Three bits. Version number of the protocol.
// mode. Three bits. Client will pick mode 3 for client.
ntp->stratum=0; // Eight bits. Stratum level of the local clock.
ntp->poll=0; // Eight bits. Maximum interval between successive messages.
ntp->precision=0; // Eight bits. Precision of the local clock.
ntp->rootDelay=0; // 32 bits. Total round trip delay time.
ntp->rootDispersion=0; // 32 bits. Max error aloud from primary clock source.
ntp->refId=0; // 32 bits. Reference clock identifier.
ntp->refTm_s=0; // 32 bits. Reference time-stamp seconds.
ntp->refTm_f=0; // 32 bits. Reference time-stamp fraction of a second.
ntp->origTm_s=0; // 32 bits. Originate time-stamp seconds.
ntp->origTm_f=0; // 32 bits. Originate time-stamp fraction of a second.
ntp->rxTm_s=0; // 32 bits. Received time-stamp seconds.
ntp->rxTm_f=0; // 32 bits. Received time-stamp fraction of a second.
ntp->txTm_s=0; // 32 bits and the most important field the client cares about. Transmit time-stamp seconds.
ntp->txTm_f=0; // 32 bits. Transmit time-stamp fraction of a second.
return udp_generic(dev, ip, src, dst, pos,end);
}
uint32_t ntp_incoming(uint8_t* start, uint8_t *pos)
{
struct udp_v4_ntp *ntp=pos;
klog("0x%08X",ntohl(ntp->txTm_s)); // timestamp recevived
klog("google's NTP says that %d seconds elapsed since 1 jan 1970",ntohl(ntp->txTm_s)); // timestamp recevived
return 0; // all ok
}
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