// callback : have received a Pdu from the target host with given read comm str
// this is really simplistic, but gives the general idea
int agent_impl::handle_get( Pdu &pdu, UdpTarget &target)
{
ACE_TRACE("agent_impl::handle_get");
OctetStr mgr_rd_str, agent_rd_str;
target.get_read_community(mgr_rd_str); // requster's read community string
tgt_.get_read_community(agent_rd_str); // this agent's read community string
// 1. verify we have a valid read string else drop pdu (no response to caller)
if (mgr_rd_str != agent_rd_str) {
ACE_DEBUG((LM_DEBUG, "agent_impl::handle_get: invalid read community recvd\n"));
return 0;
}
// 2. iterate over each varbind in the pdu, filling providing responses
int fdone = 0;
for (int i = 0; (i < pdu.get_vb_count()) && !fdone; i++) {
Vb vb;
pdu.get_vb(vb, i);
if (get_response(vb)) { // set a value for the oid if we can else
set_error_status(&pdu, SNMP_ERROR_NO_SUCH_NAME); // these ought to be member
set_error_index(&pdu, i); // functions but are not yet...
fdone++; // trigger flag to exit loop early
}
else // failed, return noSuch error
pdu.set_vb(vb, i);
}
// 3. lastly, return the pkt to the caller
return respond(pdu, target);
}
wpdu::wpdu(const Pdu& pdu, const UdpTarget& target):
valid_flag_(SNMP_CLASS_INVALID ), comm_len(MAX_COMM_STR_LEN)
{
reset_iov(iovec_);
version_ = target.get_version();
int status;
OctetStr comm_str;
community_name[0] = 0;
snmp_pdu *raw_pdu; // create a raw pdu
raw_pdu = cmu_snmp::pdu_create( (int) pdu.get_type());
if (!raw_pdu) {
valid_flag_ = SNMP_CLASS_RESOURCE_UNAVAIL;
return;
}
raw_pdu->reqid = pdu.get_request_id();
raw_pdu->errstat= (unsigned long) pdu.get_error_status();
raw_pdu->errindex= (unsigned long) pdu.get_error_index();
switch (raw_pdu->command) {
case sNMP_PDU_GET:
case sNMP_PDU_GETNEXT:
target.get_read_community(comm_str);
break;
case sNMP_PDU_SET:
target.get_write_community(comm_str);
break;
case sNMP_PDU_V1TRAP:
target.get_read_community(comm_str);
if (set_trap_info(raw_pdu, pdu)) // will free raw_pdu
return;
break;
case sNMP_PDU_RESPONSE:
break;
default:
ACE_ASSERT(0);
return;
}
if (load_vbs(raw_pdu, pdu)) {
cmu_snmp::free_pdu( raw_pdu);
valid_flag_ = SNMP_CLASS_RESOURCE_UNAVAIL;
return;
}
// TODO: determine how big raw_pdu serializes out to
iovec_.iov_len = target.get_max_pdu_size();
ACE_NEW(iovec_.iov_base, char [iovec_.iov_len]);
// create raw byte stream
// The intermediate integer is to avoid type-punned pointer
// dereferencing.
int out_length = iovec_.iov_len;
status = cmu_snmp::build( raw_pdu,
(unsigned char *)iovec_.iov_base,
&out_length,
target.get_version(),
comm_str.data(),
comm_str.length());
iovec_.iov_len = out_length;
if ( status != 0) {
valid_flag_ = SNMP_ERROR_WRONG_ENCODING;
cmu_snmp::free_pdu( raw_pdu);
return;
}
cmu_snmp::free_pdu( raw_pdu);
valid_flag_ = SNMP_CLASS_SUCCESS;
}