Go snmp server#20

[upsampled]

Fixed #20 working with gosnmp/gosnmp mainline

Also works with SHA256/AES256, to test this:

• ensure you have compiled net-snmp to support more advanced hash/cipher

$snmpwalk -h 2>&1 | grep "\-x\|\-a"
  -a PROTOCOL           set authentication protocol (MD5|SHA|SHA-224|SHA-256|SHA-384|SHA-512)
  -x PROTOCOL           set privacy protocol (DES|AES|AES-192|AES-256)

• modify gosnmpserver/main.go and run it:

AuthenticationProtocol:   gosnmp.SHA256,
PrivacyProtocol:          gosnmp.AES256,

• access the server with:

$snmpwalk -v 3 -l authPriv -n public -u testuser -a SHA-256 -A testauth -x AES-256 -X testpriv-L e 127.0.0.1:1161 1

[slayercat]

sure~

[slayercat]

I am doing some tests and found that both the TestServerTestsSuite/TestGetSetOids/SNMPWalk and TestServerTestsSuite/TestGetSetOids/SNMPSet tests have failed. I am still investigating the reasons for these failures.

[upsampled]

I had some time this morning to look into this, below is a stand alone program that runs the server for the test. Here is what I found:

TestServerTestsSuite/TestGetSetOids/SNMPWalk

When I run snmpwalk -v2c -c public localhost:6161 1 on a server configured the same way as the test I get the following:

$ snmpwalk -v2c -c public localhost:6161 1
iso.2.3.1 = INTEGER: 0
iso.2.3.2 = NULL
iso.2.3.3 = ""
iso.2.3.4 = OID: iso.2.3.4
iso.2.3.6 = Counter32: 0
iso.2.3.7 = Gauge32: 0
iso.2.3.8 = Timeticks: (0) 0:00:00.00
iso.2.3.9 = Counter64: 0
iso.2.3.10 = 0
Timeout: No Response from localhost:6161

So the issue is serving Oids iso.2.3.11 and iso.2.3.12. This is probably another issue with Oid sorting and lookup (IE: f220d18). I'll look into it more later.

TestServerTestsSuite/TestGetSetOids/SNMPSet/ByGoSNMP/Counter32,

it is pretty straight forward:

gosnmp currently only supports SNMP SETs for Integers, IPAddress and OctetStrings

In your fork the Set function is just

// Set sends an SNMP SET request
func (x *GoSNMP) Set(pdus []SnmpPDU) (result *SnmpPacket, err error) {
	var packetOut *SnmpPacket
	packetOut = x.mkSnmpPacket(SetRequest, pdus, 0, 0)
	return x.send(packetOut, true)
}

While gosnmp/gosnmp it is:

// Set sends an SNMP SET request
func (x *GoSNMP) Set(pdus []SnmpPDU) (result *SnmpPacket, err error) {
	var packetOut *SnmpPacket
	switch pdus[0].Type {
	// TODO test Gauge32
	case Integer, OctetString, Gauge32, IPAddress, ObjectIdentifier:
		packetOut = x.mkSnmpPacket(SetRequest, pdus, 0, 0)
	default:
		return nil, fmt.Errorf("ERR:gosnmp currently only supports SNMP SETs for Integers, IPAddress and OctetStrings")
	}
	return x.send(packetOut, true)
}

If we need to support Counter64 Set, then I'll work on getting a PR to gosnmp/gosnmp

[upsampled]

Tracking TestServerTestsSuite/TestGetSetOids/SNMPSet/ByGoSNMP/Counter32 issue in my bigger ticket gosnmp/gosnmp#448

@slayercat if you could look at TestServerTestsSuite/TestGetSetOids/SNMPWalk that be great, if not I will get around to it eventually

[slayercat]

Thank you for your investigation. I apologize for the delayed response during this time due to personal matters.

I believe that as the upstream gosnmp library improves, the set issues can gradually be resolved. Additionally, some set operations lack use cases and packet captures, so I tend to ignore TestGetSetOids/SNMPSet.

On the other hand, in the previous commit (tag v0.4), the tests for TestGetSetOids/SNMPWalk were successful. Therefore, while this could possibly be caused by an existing issue, I would like to investigate to ensure that no other problems have been introduced.

I would greatly appreciate it if you could assist in the investigation. I expect to return to normal responsiveness by October 8th.

[upsampled]

@slayercat the issue is isolated to the OpaqueFloat type (see logs in #22 ). Not sure the specifics yet.

[upsampled]

The issue is that OpaqueDouble and OpaqueFloat are having issue when set to 0

[upsampled]

Ok so far the outstanding times to get these tests working are all in gosnmp, the issues are:

• Handle 0.0 value for floats (currently in Add net-snmp validation testing gosnmp/gosnmp#452)
• Counter32 Set Support (currently in Add net-snmp validation testing gosnmp/gosnmp#452)
• Counter64 Set Support
• Null Set and Marshalling Support
• TimeTicks Support
• Uinterger32 support

[upsampled]

Ok I have everything working on GoSNMPServer's side with just that additional change to hand IP Addresses.

I have the rest of the items above working locally for gosnmp but I just need to write tests and the them accepted in the PR

[upsampled]

Ok all needed changes are in gosnmp/gosnmp#452 . If/When that is accepted all tests will pass.

[slayercat]

Thanks~ Merged.