Modules/VIARhineII - Fiddling
[tpg/acess2.git] / KernelLand / Modules / IPStack / icmp.c
1 /*
2  * Acess2 IP Stack
3  * - ICMP Handling
4  */
5 #include "ipstack.h"
6 #include "ipv4.h"
7 #include "icmp.h"
8
9 // === CONSTANTS ===
10 #define PING_SLOTS      64
11
12 // === PROTOTYPES ===
13 void    ICMP_Initialise();
14 void    ICMP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer);
15
16 // === GLOBALS ===
17 struct {
18         tInterface      *Interface;
19          int    bArrived;
20 }       gICMP_PingSlots[PING_SLOTS];
21
22 // === CODE ===
23 /**
24  * \fn void ICMP_Initialise()
25  * \brief Initialise the ICMP Layer
26  */
27 void ICMP_Initialise()
28 {
29         IPv4_RegisterCallback(IP4PROT_ICMP, ICMP_GetPacket);
30 }
31
32 /**
33  * \fn void ICMP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer)
34  * \brief Handles a packet from the IP Layer
35  */
36 void ICMP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffer)
37 {
38         tICMPHeader     *hdr = Buffer;
39         
40         //Log_Debug("ICMPv4", "Length = %i", Length);
41         Log_Debug("ICMPv4", "hdr->Type, hdr->Code = %i, %i", hdr->Type, hdr->Code);
42         //Log_Debug("ICMPv4", "hdr->Checksum = 0x%x", ntohs(hdr->Checksum));
43         Log_Debug("ICMPv4", "hdr->ID = 0x%x", ntohs(hdr->ID));
44         Log_Debug("ICMPv4", "hdr->Sequence = 0x%x", ntohs(hdr->Sequence));
45         
46         switch(hdr->Type)
47         {
48         // -- 0: Echo Reply
49         case ICMP_ECHOREPLY:
50                 if(hdr->Code != 0) {
51                         Log_Warning("ICMPv4", "Code == %i for ICMP Echo Reply, should be 0", hdr->Code);
52                         return ;
53                 }
54                 if(hdr->ID != (Uint16)~hdr->Sequence) {
55                         Log_Warning("ICMPv4", "ID and Sequence values do not match");
56                         //return ;
57                 }
58                 gICMP_PingSlots[hdr->ID].bArrived = 1;
59                 break;
60         
61         // -- 3: Destination Unreachable
62         case ICMP_UNREACHABLE:
63                 switch(hdr->Code)
64                 {
65                 case 3: // Port Unreachable
66                         Log_Debug("ICMPv4", "Destination Unreachable (Port Unreachable)");
67                         break;
68                 default:
69                         Log_Debug("ICMPv4", "Destination Unreachable (Code %i)", hdr->Code);
70                         break;
71                 }
72 //              IPv4_Unreachable( Interface, hdr->Code, htons(hdr->Length)-sizeof(tICMPHeader), hdr->Data );
73                 break;
74         
75         // -- 8: Echo Request
76         case ICMP_ECHOREQ:
77                 if(hdr->Code != 0) {
78                         Log_Warning("ICMPv4", "Code == %i for ICMP Echo Request, should be 0", hdr->Code);
79                         return ;
80                 }
81                 //Log_Debug("ICMPv4", "Replying");
82                 hdr->Type = ICMP_ECHOREPLY;
83                 hdr->Checksum = 0;
84                 hdr->Checksum = htons( IPv4_Checksum( (Uint16*)hdr, Length/2 ) );
85                 //Log_Debug("ICMPv4", "Checksum = 0x%04x", hdr->Checksum);
86                 
87                 tIPStackBuffer  *buffer = IPStack_Buffer_CreateBuffer(1 + IPV4_BUFFERS);
88                 IPStack_Buffer_AppendSubBuffer(buffer, Length, 0, hdr, NULL, NULL);
89                 IPv4_SendPacket(Interface, *(tIPv4*)Address, 1, ntohs(hdr->Sequence), buffer);
90                 IPStack_Buffer_DestroyBuffer(buffer);
91                 break;
92         default:
93                 break;
94         }
95         
96 }
97
98 /**
99  * \brief Sends ICMP Echo and waits for the reply
100  * \note Times out after \a Interface->TimeoutDelay has elapsed
101  */
102 int ICMP_Ping(tInterface *Interface, tIPv4 Addr)
103 {
104         Sint64  ts;
105         Sint64  end;
106         char    buf[32] = "\x8\0\0\0\0\0\0\0Acess2 I"
107                       "P/TCP Stack 1.0\0";
108         tICMPHeader     *hdr = (void*)buf;
109          int    i;
110         
111         for(;;)
112         {
113                 for(i=0;i<PING_SLOTS;i++)
114                 {
115                         if(gICMP_PingSlots[i].Interface == NULL)        break;
116                 }
117                 if( i < PING_SLOTS )    break;
118                 Threads_Yield();
119         }
120         gICMP_PingSlots[i].Interface = Interface;
121         gICMP_PingSlots[i].bArrived = 0;
122         hdr->ID = i;
123         hdr->Sequence = ~i;
124         hdr->Checksum = htons( IPv4_Checksum((Uint16*)buf, sizeof(buf)) );
125         
126         ts = now();
127         
128         tIPStackBuffer  *buffer = IPStack_Buffer_CreateBuffer(1 + IPV4_BUFFERS);
129         IPStack_Buffer_AppendSubBuffer(buffer, sizeof(buf), 0, buf, NULL, NULL);
130         IPv4_SendPacket(Interface, Addr, 1, i, buffer);
131         IPStack_Buffer_DestroyBuffer(buffer);
132         
133         end = ts + Interface->TimeoutDelay;
134         while( !gICMP_PingSlots[i].bArrived && now() < end)     Threads_Yield();
135         
136         if(now() >= end)
137                 return -1;
138         
139         return (int)( now() - ts );
140 }

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