snmpvacm
(1)
Name
snmpvacm - based Access
Control entries on a network entity
Synopsis
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
NOTIFYVIEW
snmpvacm [COMMON OPTIONS] deleteAccess GROUPNAME [CON-
TEXTPREFIX] MODEL LEVEL
snmpvacm [COMMON OPTIONS] createAuth GROUPNAME [CONTEXTPRE-
FIX] MODEL LEVEL AUTHTYPE CONTEXTMATCH VIEW
snmpvacm [COMMON OPTIONS] deleteAuth GROUPNAME [CONTEXTPRE-
FIX] MODEL LEVEL AUTHTYPE
Description
Net-SNMP SNMPVACM(1)
NAME
snmpvacm - creates and maintains SNMPv3 View-based Access
Control entries on a network entity
SYNOPSIS
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
NOTIFYVIEW
snmpvacm [COMMON OPTIONS] deleteAccess GROUPNAME [CON-
TEXTPREFIX] MODEL LEVEL
snmpvacm [COMMON OPTIONS] createAuth GROUPNAME [CONTEXTPRE-
FIX] MODEL LEVEL AUTHTYPE CONTEXTMATCH VIEW
snmpvacm [COMMON OPTIONS] deleteAuth GROUPNAME [CONTEXTPRE-
FIX] MODEL LEVEL AUTHTYPE
DESCRIPTION
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. These
snmpvacm 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 ta-
ble, 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 createSec2Group command (or equivalent).
createView [-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 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 subtree
should 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 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.
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MASK
A 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. The
entry to be removed is indexed by the NAME and SUBTREE val-
ues, which should match those used in the corresponding cre-
ateView 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 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
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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 authNo-
Priv 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 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 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 cur-
rently supported.
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deleteAccess GROUPNAME [CONTEXTPREFIX] MODEL LEVEL
Delete an entry from the SNMPv3 access table, thus removing
the specified access control settings. The entry to be
removed 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. The
interpretation 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 be
removed 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 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" 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).
LIMITATIONS
This 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
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provide the full flexibility of the equivalent config file
directives.
There is (currently) no equivalent to the one-shot configure
directives rouser and rwuser.
ATTRIBUTES
See attributes(5) for descriptions of the following
attributes:
+---------------+-----------------------------------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------------------------------------+
|Availability | system/management/snmp/net-snmp/documentation |
+---------------+-----------------------------------------------+
|Stability | Volatile |
+---------------+-----------------------------------------------+
SEE ALSO
snmpcmd(1), snmpusm(1), snmpd.conf(5), snmp.conf(5), RFC
2575, Net-SNMP project FAQ
NOTES
This software was built from source available at
https://java.net/projects/solaris-userland. The original
community source was downloaded from
http://ftp.ntua.gr/mirror/net-snmp/OldFiles/net-
snmp-5.4.x/5.4.1/net-snmp-5.4.1.tar.gz
Further information about this software can be found on the
open source community website at http://www.net-snmp.org/.
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