Diff: ping.h

Revision:

0:16bcf70d262e

Child:

1:a2f7adf6db3d

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ping.h	Sat Jan 21 23:05:11 2017 +0000
@@ -0,0 +1,146 @@
+#ifndef _PING_H_
+#define _PING_H_
+
+#include "lwip/opt.h"
+#include "lwip/mem.h"
+#include "lwip/raw.h"
+#include "lwip/icmp.h"
+#include "lwip/netif.h"
+#include "lwip/sys.h"
+#include "lwip/timers.h"
+#include "lwip/inet_chksum.h"
+#include "lwip/sockets.h"
+#include "lwip/inet.h"
+
+#ifndef PING_RCV_TIMEO                              //ping timeout... geen antwoord binnen deze tijd => timeout request
+#define PING_RCV_TIMEO 1000
+#endif
+
+#ifndef PING_ID
+#define PING_ID        0x2601                       //identifier om te matchen (antwoord matched hiermee. Linux => uniek, Windows => vast, maar wel verschillend per vesrie), subtiele hint 2601 voor beter resultaat? :)
+#endif
+
+#ifndef PING_DATA_SIZE                              //grootte payload: "random" data die ook gematched moet worden in het antwoord
+#define PING_DATA_SIZE 32
+#endif
+
+#ifndef PING_DELAY                                  
+#define PING_DELAY     500
+#endif
+
+#ifndef PING_RESULT
+#define PING_RESULT(ping_ok)
+#endif
+
+static void v_PingOntvang( int32_t l_SocketReturn );
+static void v_MaakPingRequest( struct icmp_echo_hdr *x_ICMPEchoHdr, uint16_t us_Lenght );
+static err_t ux_Ping( int32_t l_SocketReturn, ip_addr_t *x_IPAddr );
+static uint16_t us_PingSequenceNummer;
+
+static void v_MaakPingRequest( struct icmp_echo_hdr *x_ICMPEchoHdr, uint16_t us_Lenght )
+{
+    int32_t ul_I;
+    int32_t ul_DataLenght;
+    ul_DataLenght = us_Lenght - sizeof( struct icmp_echo_hdr );
+
+    ICMPH_TYPE_SET( x_ICMPEchoHdr, ICMP_ECHO );
+    ICMPH_CODE_SET( x_ICMPEchoHdr, 0 );
+    x_ICMPEchoHdr->chksum = 0;
+    x_ICMPEchoHdr->id     = PING_ID;
+    x_ICMPEchoHdr->seqno  = htons( ++us_PingSequenceNummer );                                   //byte order to netwerk byte order
+
+    for( ul_I = 0; ul_I < ul_DataLenght; ul_I++ )                                             //beetje "random" data erin gooien
+    {
+        ( ( char* ) x_ICMPEchoHdr )[sizeof( struct icmp_echo_hdr ) + ul_I] = ( char )ul_I;
+    }
+
+    x_ICMPEchoHdr->chksum = inet_chksum( x_ICMPEchoHdr, us_Lenght );
+}
+
+static err_t ux_Ping( int32_t l_SocketReturn, ip_addr_t *x_IPAddr )                                 //pingske leggen
+{
+    int32_t l_Err;
+    struct icmp_echo_hdr *x_ICMPEchoHdr;
+    struct sockaddr_in x_VerzendAddr;
+    int32_t l_PingGrootte;
+    
+    l_PingGrootte = sizeof( struct icmp_echo_hdr ) + PING_DATA_SIZE;
+    x_ICMPEchoHdr = ( struct icmp_echo_hdr * ) mem_malloc( ( mem_size_t ) l_PingGrootte );          //mallocske doen, is helaas niet toegelaten volgens mistra C :(
+                                                                                                    //mem_size_t afhankelijk van hoe groot, uint16_t of uint32_t is van type size_t => malloc heeft verwacht size_t => unsigned type
+    if( !x_ICMPEchoHdr )                                                                            //heeft ni veel nut dat functie verdergaat en error gooit als Echo failed
+    {
+        return ERR_MEM;                                                                             //Out Of memory errorke geven
+    }
+
+    v_MaakPingRequest( x_ICMPEchoHdr, ( uint16_t ) l_PingGrootte ); 
+
+    x_VerzendAddr.sin_len = sizeof( x_VerzendAddr );
+    x_VerzendAddr.sin_family = AF_INET;
+    inet_addr_from_ipaddr( &x_VerzendAddr.sin_addr, x_IPAddr );
+    l_Err = lwip_sendto( l_SocketReturn, x_ICMPEchoHdr, l_PingGrootte, 0, ( struct sockaddr* ) &x_VerzendAddr, sizeof( x_VerzendAddr ) );
+
+    mem_free( x_ICMPEchoHdr );
+
+    return ( l_Err ? ERR_OK : ERR_VAL );
+}
+
+static void v_PingOntvang( int32_t l_SocketReturn )
+{
+    char c_Buffer[64];
+    uint32_t ul_FromLen;
+    uint32_t ul_RecvLen;
+    struct sockaddr_in x_OntvangAdres;
+    struct ip_hdr *px_IPHdr;
+    struct icmp_echo_hdr *pux_Echo;
+    ip_addr_t x_RecvAddr;
+    
+    ul_RecvLen = lwip_recvfrom( l_SocketReturn, c_Buffer, sizeof( c_Buffer ), 0, ( struct sockaddr* ) &x_OntvangAdres, ( socklen_t* ) &ul_FromLen);
+    
+    while( ul_RecvLen > 0 ) 
+    {
+        if( ul_RecvLen >=  sizeof( struct ip_hdr ) + sizeof( struct icmp_echo_hdr ) );
+        {        
+            inet_addr_to_ipaddr(&x_RecvAddr, &x_OntvangAdres.sin_addr);
+            
+            px_IPHdr = ( struct ip_hdr * ) c_Buffer;
+            pux_Echo = ( struct icmp_echo_hdr * ) ( c_Buffer + ( IPH_HL( px_IPHdr ) * 4));
+            
+            if( ( pux_Echo->id == PING_ID ) && ( pux_Echo->seqno == htons( us_PingSequenceNummer ) ) )                  //matchen van data, byte order naar netwerk byte order
+            {
+                PING_RESULT( ( ICMPH_TYPE( iecho ) == ICMP_ER ) );                                                      //ping resultaat processen
+                return;
+            } 
+        }
+        
+        ul_RecvLen = lwip_recvfrom( l_SocketReturn, c_Buffer, sizeof( c_Buffer ), 0, ( struct sockaddr* ) &x_OntvangAdres, ( socklen_t* ) &ul_FromLen );
+    }
+    
+    PING_RESULT( 0 );                                                                        //ping resultaat processen
+}
+
+void v_Ping( void )
+{
+    int32_t l_SocketReturn;                                                                //vooral om te kunnen debuggen binnen LWIP, sockets.c ... -1 on fail
+    uint32_t ul_TimeOut;
+    
+    l_SocketReturn = lwip_socket( AF_INET, SOCK_RAW, IP_PROTO_ICMP );
+    ul_TimeOut = PING_RCV_TIMEO;
+
+    if( l_SocketReturn  > -1 ) 
+    {
+        lwip_setsockopt( l_SocketReturn, SOL_SOCKET, SO_RCVTIMEO, &ul_TimeOut, sizeof( ul_TimeOut ) );
+
+        while ( 1 ) 
+        {
+            ip_addr_t x_PingTarget = { 0x08080808 };                                              //Google DNS server, uptime 99.9% => vrij betrouwbaar om naar heen te pingen. Behalve in landen zoals DPRK
+           
+            if ( ux_Ping( l_SocketReturn, &x_PingTarget ) == ERR_OK ) 
+            {
+                v_PingOntvang( l_SocketReturn );
+            } 
+            sys_msleep( PING_DELAY );
+        }
+    }
+}
+
+#endif