Net-SNMP SNMPVACM(1)
NAME
snmpvacm - creates and maintains SNMPv3 View-based Access
Control entries on a network entitySYNOPSIS
snmpvacm [COMMON OPTIONS] createSec2Group MODEL SECURITYNAME
GROUPNAME
snmpvacm [COMMON OPTIONS] deleteSec2Group MODEL SECURITYNAME
snmpvacm [COMMON OPTIONS] createView [-Ce] NAME SUBTREE MASK
snmpvacm [COMMON OPTIONS] deleteView NAME SUBTREE
snmpvacm [COMMON OPTIONS] createAccess GROUPNAME [CON-
TEXTPREFIX] MODEL LEVEL CONTEXTMATCH READVIEW WRITEVIEW
NOTIFYVIEWsnmpvacm [COMMON OPTIONS] deleteAccess GROUPNAME [CON-
TEXTPREFIX] MODEL LEVELsnmpvacm [COMMON OPTIONS] createAuth GROUPNAME [CONTEXTPRE-
FIX] MODEL LEVEL AUTHTYPE CONTEXTMATCH VIEW
snmpvacm [COMMON OPTIONS] deleteAuth GROUPNAME [CONTEXTPRE-
FIX] MODEL LEVEL AUTHTYPEDESCRIPTION
snmpvacm is an SNMP application that can be used to do sim-
ple maintenance 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. Thesesnmpvacm commands effectively create or delete rows in the
appropriate one of these tables, and match the equivalent configure directives which are documented in the snmpd.conf(5) man page. A fuller explanation of how these operate can be found in the project FAQ.SUB-COMMANDS
createSec2Group 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)
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SECURITYNAME
A string representing the security name for a principal(represented 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 createAccess below).deleteSec2Group 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 MODELand SECURITYNAME values, which should match those used in
the corresponding createSec2Group command (or equivalent).createView [-Ce] NAME SUBTREE MASK
Create an entry in the SNMPv3 MIB view table. A MIB viewconsists of a family of view subtrees which may be individu-
ally included in or (occasionally) excluded from the view.Each view subtree is defined by a combination of an OID sub-
tree 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 subtreeshould be excluded from the named view. If not speci-
fied, the default is to include the subtree in the view. When constructing a view from a mixture of included and excluded subtrees, the excluded subtreesshould 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. V5.4.1 Last change: 30 May 2003 2Net-SNMP SNMPVACM(1)
MASKA bit mask indicating which sub-identifiers of the
associated subtree OID should be regarded as signifi-
cant.deleteView 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. Theentry to be removed is indexed by the NAME and SUBTREE
values, which should match those used in the corresponding createView 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.createAccess GROUPNAME [CONTEXTPREFIX] MODEL LEVEL CONTEXTMATCH
Create an entry in the SNMPv3 access table, thus allowing a certain level of access to particular MIB views for the principals in the specified 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 createSec2Group 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 ofthe 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 V5.4.1 Last change: 30 May 2003 3Net-SNMP SNMPVACM(1)
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 thislevel or higher (where authPriv is higher than auth-
NoPriv 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 CON-
TEXTPREFIX 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 arequest 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 createView 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 createView 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 createView or equivalent) defining the MIB objects which may be included in notification request. Note that this aspect of access control is not currently supported. V5.4.1 Last change: 30 May 2003 4Net-SNMP SNMPVACM(1)
deleteAccess GROUPNAME [CONTEXTPREFIX] MODEL LEVEL
Delete an entry from the SNMPv3 access table, thus removing the specified access control settings. The entry to beremoved is indexed by the group name, context prefix, secu-
rity model and security level values, which should match those used in the corresponding createAccess command (or equivalent).createAuth GROUPNAME [CONTEXTPREFIX] MODEL LEVEL AUTHTYPE
Create an entry in the Net-SNMP extension to the standard
access table, thus allowing a certain type of access to the MIB view for the principals in the specified group. Theinterpretation of GROUPNAME, CONTEXTPREFIX, MODEL, LEVEL and
CONTEXTMATCH are the same as for the createAccess directive.
The extension access table is indexed by the group name, context prefix, security model, security level and authtype values. AUTHTYPE The style of access that this entry should be applied to. See snmpd.conf(5) and snmptrapd.conf(5) for details of valid tokens. VIEW The name of the MIB view (as set up by createView or equivalent) defining the MIB objects for which this style of access is authorized.deleteAuth GROUPNAME [CONTEXTPREFIX] MODEL LEVEL AUTHTYPE
Delete an entry from the extension access table, thus remov-
ing the specified access control settings. The entry to beremoved is indexed by the group name, context prefix, secu-
rity model, security level and authtype values, which should match those used in the corresponding createAuth command (or equivalent).EXAMPLES
Given a pre-existing user dave (which could be set up using
the snmpusm(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
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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 inthe 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" containingthe (pre-existing) user "wes", a new view "sysView" contain-
ing 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). EXIT STATUS 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). LIMITATIONSThis utility does not support the configuration of new com-
munity 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 secLevel and contextMatch parameters is less than intuitive. These commands do not V5.4.1 Last change: 30 May 2003 6Net-SNMP SNMPVACM(1)
provide the full flexibility of the equivalent config file directives.There is (currently) no equivalent to the one-shot configure
directives rouser and rwuser.SEE ALSO
snmpcmd(1), snmpusm(1), snmpd.conf(5), snmp.conf(5), RFC2575, Net-SNMP project FAQ
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:_______________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|____________________|__________________________________|_
| Availability | system/management/snmp/net-snmp|
|____________________|__________________________________|_
| Interface Stability| Volatile ||____________________|_________________________________|
NOTESSource for net-snmp is available on http://opensolaris.org.
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