/*
SNMP management daemon for the Discworld Mudlib.
Technically this daemon responds with v1 as it's protocol.
However it does not support the full MIB-II spec mainly because a lot
of it is not relevant to the information I wanted to advertise.
Everything is advertised via the system entity in MIB-II using the
identifiers 101 and up. OID 100 is there as a dummy, it returns 0 and is
for mrtg which requires 2 mibs to graph.
So, for example, number of players on is numPlayers or 1.3.6.1.2.1.1.101
*/
#include "socket.h"
#include "socket_errors.h"
#include "snmp.h"
int s;
class SnmpMessage {
int version;
string community;
string SourceAddress;
int RequestType;
int *PacketID;
int ErrorStatus;
int ErrorIndex;
buffer *ObjectData;
}
void WriteBuffer(string what, buffer tbuf)
{
string tstr;
int ti;
tstr="";
for(ti=0;ti<sizeof(tbuf);ti++)
{
tstr+=sprintf("%X ", tbuf[ti]);
}
tell_creator("sojan", "Buffer %s: %s\n", what, tstr);
}
void create()
{
int tmp;
s=socket_create(DATAGRAM_BINARY, "ReceiveData");
tmp=socket_bind(s, LISTEN_PORT);
}
void SendReply(class SnmpMessage Reply)
{
buffer ReplyBuf, RealReplyBuf, tmpbuf;
int i,j,k,l,m;
ReplyBuf=allocate_buffer(500);
ReplyBuf[0]=SEQUENCE;
ReplyBuf[1]=0;
ReplyBuf[2]=INTEGER;
ReplyBuf[3]=1;
ReplyBuf[4]=Reply->version;
ReplyBuf[5]=OCTET_STRING;
ReplyBuf[6]=sizeof(Reply->community);
i=write_buffer(ReplyBuf, 7, Reply->community);
i=sizeof(Reply->community)+7;
ReplyBuf[i]=Reply->RequestType;
ReplyBuf[i+1]=0;
ReplyBuf[i+2]=2;
ReplyBuf[i+3]=sizeof(Reply->PacketID);
k=i+4;
for(j=0;j<sizeof(Reply->PacketID);j++)
{
ReplyBuf[k]=Reply->PacketID[j];
k++;
}
ReplyBuf[k]=2;
ReplyBuf[k+1]=1;
ReplyBuf[k+2]=0;
ReplyBuf[k+3]=2;
ReplyBuf[k+4]=1;
ReplyBuf[k+5]=0;
ReplyBuf[k+6]=SEQUENCE;
ReplyBuf[k+7]=0;
l=k+8;
for(j=0;j<sizeof(Reply->ObjectData);j++)
{
m=write_buffer(ReplyBuf, l, Reply->ObjectData[j]);
l=l+sizeof(Reply->ObjectData[j]);
}
ReplyBuf[1]=l-2;
ReplyBuf[k+7]=l-(k+8);
RealReplyBuf=allocate_buffer(l);
RealReplyBuf=ReplyBuf[0..l-1];
RealReplyBuf[i+1]=sizeof(RealReplyBuf)-i-2;
socket_write(s, RealReplyBuf, Reply->SourceAddress);
return;
}
void ParseObjects(class SnmpMessage CurrentMessage)
{
int i,j;
class SnmpMessage MyReply;
buffer mibdata;
MyReply=new(
class SnmpMessage,
version:CurrentMessage->version,
community:CurrentMessage->community,
RequestType:GETRESPONSEPDU,
SourceAddress:CurrentMessage->SourceAddress,
PacketID:CurrentMessage->PacketID,
ErrorStatus:0,
ErrorIndex:0,
ObjectData:({})
);
for(i=0;i<sizeof(CurrentMessage->ObjectData);i++)
{
j=CurrentMessage->ObjectData[i][1];
mibdata=SNMPHANDLER->GetData(CurrentMessage->ObjectData[i][2..j+1]);
if(mibdata[0]==SEQUENCE) MyReply->ObjectData+=({mibdata,});
}
SendReply(MyReply);
return;
}
void ReceiveData(int fd, buffer message, string address)
{
int i,j,k,ss,is,id,es,ei;
class SnmpMessage NewMessage;
id=0;
es=0;
ei=0;
is=0;
ss=0;
NewMessage=new(
class SnmpMessage,
version:message[4],
community:read_buffer(message, 7, message[6]),
RequestType:message[message[6]+7],
SourceAddress:address,
PacketID:({}),
ErrorStatus:0,
ErrorIndex:0,
ObjectData:({})
);
for(i=message[6]+9;i<message[1]+2;i++)
{
switch(message[i])
{
case INTEGER :
switch(is)
{
case ID :
i++;
k=i;
is++;
for(j=0;j<message[k];j++)
{
i++;
NewMessage->PacketID+=({message[i],});
}
break;
case ES :
i++;
i++;
is++;
NewMessage->ErrorStatus=message[i];
break;
case EI :
i++;
i++;
is++;
NewMessage->ErrorIndex=message[i];
break;
}
break;
case SEQUENCE :
if(!ss)
{
ss++;
i++;
break;
}
i++;
j=message[i];
i++;
NewMessage->ObjectData+=({message[i..(i+j-1)],});
break;
}
}
ParseObjects(NewMessage);
return;
}
