Manual Pages for UNIX Darwin command on man snmpvacm

SNMPVACM(1) Net-SNMP SNMPVACM(1)

NAME

snmpvacm - creates and maintains SNMPv3 View-based Access Control

entries on a network entity

SYNOPSIS

ssnnmmppvvaaccmm [COMMON OPTIONS] ccrreeaatteeSSeecc22GGrroouupp MODEL SECURITYNAME GROUPNAME

ssnnmmppvvaaccmm [COMMON OPTIONS] ddeelleetteeSSeecc22GGrroouupp MODEL SECURITYNAME

ssnnmmppvvaaccmm [COMMON OPTIONS] ccrreeaatteeVViieeww [-Ce] NAME SUBTREE MASK

ssnnmmppvvaaccmm [COMMON OPTIONS] ddeelleetteeVViieeww NAME SUBTREE

ssnnmmppvvaaccmm [COMMON OPTIONS] ccrreeaatteeAAcccceessss GROUPNAME [CONTEXTPREFIX] MODEL

LEVEL CONTEXTMATCH READVIEW WRITEVIEW NOTIFYVIEW

ssnnmmppvvaaccmm [COMMON OPTIONS] ddeelleetteeAAcccceessss GROUPNAME [CONTEXTPREFIX] MODEL

LEVEL

DESCRIPTION

ssnnmmppvvaaccmm is an SNMP application that can be used to do simple mainte-

nance on the View-based Control Module (VACM) tables of an SNMP agent.

The SNMPv3 VACM specifications (see RFC2575) define assorted tables to specify groups of users, MIB views, and authorised access settings.

These ssnnmmppvvaaccmm commands effectively create or delete rows in the appro-

priate one of these tables, and match the equivalent configure direc-

tives which are documented in the snmpd.conf(5) man page. A fuller explanation of how these operate can be found in the project FAQ.

SSUUBB-CCOOMMMMAANNDDSS

ccrreeaatteeSSeecc22GGrroouupp MODEL SECURITYNAME GROUPNAME

Create an entry in the SNMPv3 security name to group table. This table allows a single access control entry to be applied to a number of users (or 'principals'), and is indexed by the security model and security name values. MODEL An integer representing the security model, taking one of the following values:

1 - reserved for SNMPv1

2 - reserved for SNMPv2c

3 - User-based Security Model (USM)

SECURITYNAME

A string representing the security name for a principal (repre-

sented in a security-model-independent format). For USM-based

requests, the security name is the same as the username.

GROUPNAME

A string identifying the group that this entry (i.e. security name/model pair) should belong to. This group name will then be referenced in the access table (see ccrreeaatteeAAcccceessss below).

ddeelleetteeSSeecc22GGrroouupp MODEL SECURITYNAME

Delete an entry from the SNMPv3 security name to group table, thus removing access control settings for the given principal. The entry to

be removed is indexed by the MODEL and SECURITYNAME values, which

should match those used in the corresponding ccrreeaatteeSSeecc22GGrroouupp command (or equivalent).

ccrreeaatteeVViieeww [-Ce] NAME SUBTREE MASK

Create an entry in the SNMPv3 MIB view table. A MIB view consists of a

family of view subtrees which may be individually included in or (occa-

sionally) excluded from the view. Each view subtree is defined by a combination of an OID subtree together with a bit string mask. The view table is indexed by the view name and subtree OID values.

[-Ce]

An optional flag to indicate that this view subtree should be excluded from the named view. If not specified, the default is to include the subtree in the view. When constructing a view from a mixture of included and excluded subtrees, the excluded

subtrees should be defined first - particularly if the named

view is already referenced in one or more access entries.

NAME

A string identifying a particular MIB view, of which this OID subtree/mask forms part (possibly the only part). SUBTREE The OID defining the root of the subtree to add to (or exclude from) the named view. MASK

A bit mask indicating which sub-identifiers of the associated

subtree OID should be regarded as significant.

ddeelleetteeVViieeww NAME SUBTREE

Delete an entry from the SNMPv3 view table, thus removing the subtree from the given MIB view. Removing the final (or only) subtree will result in the deletion of the view. The entry to be removed is indexed

by the NAME and SUBTREE values, which should match those used in the

corresponding ccrreeaatteeVViieeww command (or equivalent). When removing subtrees from a mixed view (i.e. containing both included and excluded subtrees), the included subtrees should be removed first.

ccrreeaatteeAAcccceessss GROUPNAME [CONTEXTPREFIX] MODEL LEVEL CONTEXTMATCH READVIEW

WRITEVIEW NOTIFYVIEW Create an entry in the SNMPv3 access table, thus allowing a certain

level of access to particular MIB views for the principals in the spec-

ified group (given suitable security model and levels in the request). The access table is indexed by the group name, context prefix, security model and security level values.

GROUPNAME

The name of the group that this access entry applies to (as set up by a ccrreeaatteeSSeecc22GGrroouupp command, or equivalent)

CONTEXTPREFIX

A string representing a context name (or collection of context names) which this access entry applies to. The interpretation

of this string depends on the value of the CONTEXTMATCH field

(see below). If omitted, this will default to the null context "". MODEL An integer representing the security model, taking one of the following values:

1 - reserved for SNMPv1

2 - reserved for SNMPv2c

3 - User-based Security Model (USM)

LEVEL An integer representing the minimal security level, taking one of the following values:

1 - noAuthNoPriv

2 - authNoPriv

3 - authPriv

This access entry will be applied to requests of this level or higher (where authPriv is higher than authNoPriv which is in turn higher than noAuthNoPriv).

CONTEXTMATCH

Indicates how to interpret the CONTEXTPREFIX value. If this

field has the value '1' (representing 'exact') then the context

name of a request must match the CONTEXTPREFIX value exactly for

this access entry to be applicable to that request. If this field has the value '2' (representing 'prefix') then the initial substring of the context name of a request must match

the CONTEXTPREFIX value for this access entry to be applicable

to that request. This provides a simple form of wildcarding. READVIEW The name of the MIB view (as set up by ccrreeaatteeVViieeww or equivalent) defining the MIB objects for which this request may request the current values. If there is no view with this name, then read access is not granted. WRITEVIEW The name of the MIB view (as set up by ccrreeaatteeVViieeww or equivalent) defining the MIB objects for which this request may potentially SET new values. If there is no view with this name, then read access is not granted. NOTIFYVIEW The name of the MIB view (as set up by ccrreeaatteeVViieeww or equivalent) defining the MIB objects which may be included in notification request.

Note that this aspect of access control is not currently sup-

ported.

ddeelleetteeAAcccceessss GROUPNAME [CONTEXTPREFIX] MODEL LEVEL

Delete an entry from the SNMPv3 access table, thus removing the speci-

fied access control settings. The entry to be removed is indexed by

the group name, context prefix, security model and security level val-

ues, which should match those used in the corresponding ccrreeaatteeAAcccceessss command (or equivalent). EEXXAAMMPPLLEESS

Given a pre-existing user dave (which could be set up using the snm-

pusm(1) command), we could configure full read-write access to the

whole OID tree using the commands:

snmpvacm localhost createSec2Group 3 dave RWGroup

snmpvacm localhost createView all .1 80

snmpvacm localhost createAccess RWGroup 3 1 1 all all none

This creates a new security group named "RWGroup" containing the SNMPv3 user "dave", a new view "all" containing the full OID tree based on .iso(1) , and then allows those users in the group "RWGroup" (i.e.

"dave") both read- and write-access to the view "all" (i.e. the full

OID tree) when using authenticated SNMPv3 requests.

As a second example, we could set up read-only access to a portion of

the OID tree using the commands:

snmpvacm localhost createSec2Group 3 wes ROGroup

snmpvacm localhost createView sysView system fe

snmpvacm localhost createAccess ROGroup 3 0 1 sysView none none

This creates a new security group named "ROGroup" containing the (pre-

existing) user "wes", a new view "sysView" containing just the OID tree

based on .iso(1).org(3).dod(6).inet(1).mgmt(2).mib-2(1).system(1) , and

then allows those users in the group "ROGroup" (i.e. "wes") read-

access, but not write-access to the view "sysView" (i.e. the system

group). EEXXIITT SSTTAATTUUSS The following exit values are returned:

0 - Successful completion

1 - A usage syntax error (which displays a suitable usage message) or a

request timeout.

2 - An error occurred while executing the command (which also displays

a suitable error message). LLIIMMIITTAATTIIOONNSS This utility does not support the configuration of new community strings, so is only of use for setting up new access control for SNMPv3 requests. It can be used to amend the access settings for existing community strings, but not to set up new ones. The use of numeric parameters for sseeccLLeevveell and ccoonntteexxttMMaattcchh parameters

is less than intuitive. These commands do not provide the full flexi-

bility of the equivalent config file directives.

There is (currently) no equivalent to the one-shot configure directives

rouser and rwuser.