//--------------------------------------------------------------------------
// Function Name: snmp_read
// Description : Checks to see if any of the fd's set in the fdset belong to snmp.
// Each socket with it's fd set has a packet read from it and
// snmp_parse is called on the packet received. The resulting pdu is
// passed to the callback routine for that session. If the callback
// routine returns successfully, the pdu and it's request are
// deleted.
// Return Value : NONE
// Calling To : udp_read, snmp_parse, free_pdu and user's callback
// function
// Called By : user
// Status : some part of this module should be mdoified
//-------------------------------------------------------------------------
void snmp_read (snmp_session *session)
{
uint8 inpacket[SNMP_MAX_LEN], outpacket[SNMP_MAX_LEN];
int outlength, fromlength, inlength;
inlength = SNMP_MAX_LEN;
if(udp_read(session, inpacket, &inlength)) {
snmpInPkts++ ;
outlength = SNMP_MAX_LEN;
if(snmp_agent_parse(session, inpacket, inlength, outpacket, &outlength))
{
#if defined(SNMP_DUMP) && defined(PC_OUTPUT)
{
int count;
printf("sent %d bytes to %s:\n", (int) outlength,
inet_ntoa(from.sin_addr));
for (count = 0; count < outlength; count++) {
printf("%02X ", outpacket[count]);
if ((count % 16) == 15)
printf("\n");
}
printf("\n\n");
}
#endif
if(snmp_udp_send(session, outpacket,outlength) == 0) return;
snmp_outpkts++;
#ifdef WEBADMIN
RunChangeIPAddress();
#ifndef _PC
RunWriteDataToEEPROM();
#endif
#endif WEBADMIN
}
}
}
int
snmp_read_packet(int sd)
{
struct sockaddr_in from;
int length, out_length, fromlength;
u_char packet[1500], outpacket[1500];
#ifdef USE_LIBWRAP
char *addr_string;
#endif
fromlength = sizeof from;
length = recvfrom(sd, (char *) packet, 1500, 0, (struct sockaddr *)&from,
&fromlength);
if (length == -1)
perror("recvfrom");
#ifdef USE_LIBWRAP
addr_string = inet_ntoa(from.sin_addr);
if(!addr_string) {
addr_string = STRING_UNKNOWN;
}
if(hosts_ctl("snmpd", addr_string, addr_string, STRING_UNKNOWN)) {
syslog(allow_severity, "Connection from %s", addr_string);
} else {
syslog(deny_severity, "Connection from %s refused", addr_string);
return(0);
}
#endif
#ifdef USING_MIBII_SNMP_MIB_MODULE
snmp_inpkts++;
#endif
if (snmp_dump_packet){
printf("\nreceived %d bytes from %s:\n", length,
inet_ntoa(from.sin_addr));
xdump(packet, length, "");
printf("\n");
fflush(stdout);
} else if (log_addresses){
int count;
for(count = 0; count < ADDRCACHE; count++){
if (addrCache[count].status > UNUSED /* used or old */
&& from.sin_addr.s_addr == addrCache[count].addr)
break;
}
if (count >= ADDRCACHE || verbose){
printf("%s Received SNMP packet(s) from %s\n",
sprintf_stamp(NULL), inet_ntoa(from.sin_addr));
for(count = 0; count < ADDRCACHE; count++){
if (addrCache[count].status == UNUSED){
addrCache[count].addr = from.sin_addr.s_addr;
addrCache[count].status = USED;
break;
}
}
} else {
addrCache[count].status = USED;
}
}
out_length = 1500;
if (snmp_agent_parse(packet, length, outpacket, &out_length,
from.sin_addr.s_addr)){
if (snmp_dump_packet){
printf("\nsent %d bytes to %s:\n", out_length,
inet_ntoa(from.sin_addr));
xdump(outpacket, out_length, "");
printf("\n");
fflush(stdout);
}
#ifdef USING_MIBII_SNMP_MIB_MODULE
snmp_outpkts++;
#endif
if (sendto(sd, (char *)outpacket, out_length, 0,
(struct sockaddr *)&from, sizeof(from)) < 0){
perror("sendto");
return 0;
}
}
return 1;
}
