NIS+LDAPmapping(4) (man pages section 4: File Formats)

man pages section 4: File Formats

NIS+LDAPmapping(4)

NAME

NIS+LDAPmapping– configuration file for mapping between NIS+ and LDAP

SYNOPSIS

/var/nis/NIS+LDAPmapping

DESCRIPTION

The /var/nis/NIS+LDAPmapping configuration file contains the mapping between NIS+ objects, particularly table entries, and LDAP entries and attributes. This information can come from LDAP, from this file, from the rpc.nisd(1M) command line, or from a combination of all three. The values in this file supersede those obtained from the LDAP server, but values from the command line supersede those in the file.

Each line in the file can be up to 8191 bytes long, not counting the newline. There can be an indefinite number of continuation lines. A continuation is indicated by a '\' (backslash) in the last position, immediately before the newline of a line. Characters are escaped, that is, exempted from special interpretation, when preceeded by a backslash character.

The '#' (hash) character starts a comment. White space is either ASCII space or a horizontal tab. In general, lines consist of optional white space, an attribute name, at least one white space character, and an attribute value.

EXTENDED DESCRIPTION

Getting Started

The default rpc.nisd(4) configuration file at /etc/default/rpc.nisd and the template file at /var/nis/NIS+LDAPmapping.template are sufficient for the minimum NIS+ installation. The following assumptions are made:

The NIS+ standard directories, tables, and groups created by nissetup(1M) or nisserver(1M) should be mapped. However, the timezone.org_dir and client_info.org_dir tables should not be mapped.
The NIS+ objects for which the rpc.nisd is a master are mapped both to and from LDAP.
Those NIS+ objects for which the rpc.nisd is a replica are mapped from LDAP.
The LDAP server is running on the local machine, and it can be reached at port 389 on the 127.0.0.1 IP address.
The authentication method is none, meaning that all LDAP calls, whether for reading or writing, are unauthenticated. There is no transport layer security.
The default values for TTLs and LDAP container locations and object classes are valid.
The LDAP server supports RFC 2307bis. You want to use the RFC 2307bis object classes and attributes. See NOTES
The nisplusObject attribute, the nisplusObjectContainer object class, and the ou=nisPlus container have been created.
You do not need to store or retrieve table entry owner, group owner, entry access rights, or entry object TTL in or from LDAP. For more information on these pseudo-columns, see the discussion of zo_owner, and the like, in the description of the nisplusLDAPcolumnFromAttribute attribute.
NIS+ principal names and RPC netnames (the cname and auth_name columns, respectively, in the cred.org_dir table) should be derived from the owner of the cred table. For example, if the owner is npadm.my.dom.ain., the cname and auth_name values for entries created from LDAP data will be of the form:
```
user-or-host.my.dom.ain.
```
and
```
unix.uid-or-host@my.dom.ain
```
respectively.

If these assumptions are true, you can enable mapping by copying the /var/nis/NIS+LDAPmapping.template file to /var/nis/NIS+LDAPmapping and restart the rpc.nisd. If you want to either upload NIS+ data to LDAP, or download LDAP data to NIS+, see the description of the nisplusLDAPinitialUpdateAction attribute on rpc.nisd(4).

If one or more of the assumptions are false, do the following:

To remove mappings, identify the database id of the NIS+ object that should not be mapped, then delete or comment out the nisplusLDAPdatabaseIdMapping, nisplusLDAPentryTtl, nisplusLDAPobjectDN, nisplusLDAPattributeFromColumn, and nisplusLDAPcolumnFromAttribute attributes for that database id.

To add mappings, find an existing mapping for a NIS+ object similar to the one you want to map, and then use that mapping as a template to create the nisplusLDAPdatabaseIdMapping, nisplusLDAPentryTtl, nisplusLDAPobjectDN, nisplusLDAPattributeFromColumn, and nisplusLDAPcolumnFromAttribute attributes for the new mapping. The new mapping must have a unique database id.

To enable mapping of the timezone or client_info tables, consult your LDAP server documentation about how to create attributes and object classes, and set up the following. The following is LDIF data for ldapadd(1). Attribute and object class OIDs are examples only.

For client_info:

dn: cn=schema
changetype: modify
add: attributetypes
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.12.0 \
   NAME 'nisplusClientInfoAttr' \
   DESC 'NIS+ client_info table client column' \
   SYNTAX 1.3.6.1.4.1.1466.115.121.1.15 SINGLE-VALUE )
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.12.1 \
   NAME 'nisplusClientInfoInfo' \
   DESC 'NIS+ client_info table info column' \
   SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 SINGLE-VALUE )
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.12.2 \
   NAME 'nisplusClientInfoFlags' \
   DESC 'NIS+ client_info table flags column' \
   SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 SINGLE-VALUE )

dn: cn=schema
changetype: modify
add: objectclasses
objectclasses:  ( 1.3.6.1.4.1.42.2.27.5.42.42.13.0 \
   NAME 'nisplusClientInfoData' \
   DESC 'NIS+ client_info table data' \
   SUP top STRUCTURAL MUST ( cn ) \
   MAY (nisplusClientInfoAttr $ nisplusClientInfoInfo $ nisplusClientInfoFlags))

For the ou=ClientInfo container, substitute your actual search base for searchBase):

dn: ou=ClientInfo,searchBase
ou: ClientInfo
objectClass: top
objectClass: organizationalUnit

For timezone:

dn: cn=schema
changetype: modify
add: attributetypes
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.15.0 NAME 'nisplusTimeZone' \
          DESC 'tzone column from NIS+ timezone table' \
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 SINGLE-VALUE )

dn: cn=schema
changetype: modify
add: objectclasses
objectclasses:  ( 1.3.6.1.4.1.42.2.27.5.42.42.16.0 NAME 'nisplusTimeZoneData' \
          DESC 'NIS+ timezone table data' \
          SUP top STRUCTURAL MUST ( cn ) \
          MAY ( nisplusTimeZone $ description ) )

For the ou=Timezone container:

dn: ou=Timezone,searchBase
ou: Timezone
objectClass: top
objectClass: organizationalUnit

Uncomment the mapping attributes for timezone and client_info in the mapping file, and restart the the rpc.nisd(1M) daemon.

To disable write mapping, edit the nisplusLDAPobjectDN value for the appropriate database id. Remove the writeObjectSpec value, leaving only the the readObjectSpec value. Make sure there are no trailing colons.

To disable read mapping, remove the readObjectSpec, leaving the database id, two colons, and the writeObjectSpec value.
Replicas cannot write-map objects. Remove disable read mapping, remove mapping entirely for the relevant database ids, as described above.
Change the preferredServerList value to the correct server address(es) and port(s). If configuration data is retrieved fromLDAP, also edit the nisplusLDAPpreferredServerList value.
Edit the authenticationMethod attribute value to the authentication method that you want to use. If configuration data is retrieved from LDAP, edit the nisplusLDAPconfigAuthenticationMethod value. If the method is anything other than none, you will need to specify one or more of the following, depending upon the method.

nisplusLDAPconfigProxyUser
nisplusLDAPproxyUser

The bind-DN to use for authentication.

nisplusLDAPconfigProxyPassword
nisplusLDAPproxyPassword

The password or key for the bind-DN and method. Make sure that the file containing the password or key is protected from access by unauthorized users.

To use transport layer security, set nisplusLDAPconfigTLS or nisplusLDAPTLS to ssl, and set nisplusLDAPconfigTLSCertificateDBPath or nisplusLDAPTLSCertificateDBPath to the file containing the certificate DB. In order to successfully use authentication and transport layer security, the server must also support the chosen values.
To change the TTLs, edit the nisplusLDAPentryTtl for the appropriate database id.

To change LDAP container locations or object classes, edit the nisplusLDAPobjectDN value for the appropriate database id.
To determine which object classes and attributes are supported, consult your LDAP server documentation. If you are using the iPlanet directory server, see idsconfig(1M) for information to set up RFC 2307bis object classes and attributes.
Refer to your LDAP server documentation for how to create attributes and object classes, and set up the following:
```
dn: cn=schema
changetype: modify
add: attributetypes
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.1.0 NAME 'nisplusObject' \
          DESC 'An opaque representation of a NIS+ object' \
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.5 SINGLE-VALUE )

dn: cn=schema
changetype: modify
add: objectclasses
objectclasses: ( 1.3.6.1.4.1.42.2.27.5.42.42.2.0 NAME 'nisplusObjectContainer' \
         SUP top STRUCTURAL DESC 'Abstraction of a NIS+ object' \
         MUST ( cn $ nisplusObject ) )
            
```
ou=nisPlus is a container assumed to reside at the defaultSearchBase. See rpc.nisd(4). The following LDIF input to ldapadd(1) will create the ou=nisPlus container. Replace dc=some,dc=domain with your actual base.
```
dn: ou=nisPlus,dc=some,dc=domain
ou: nisPlus
objectClass: top
objectClass: organizationalUnit
```
The nisplusObjectContainer, nisplusObject, and ou=nisPlus labels are suggestions. If you change nisplusObjectContainer, or ou=nisPlus, edit the mapping file to reflect this. To change nisplusObject, for example, to myObject, add nisplusObject=myObject to the filterAttrValList and attrValList portions of the readObjectSpec and writeObjectSpec of the nisplusLDAPobjectDN value for the mapping. See the description of nisplusLDAPobjectDN below.

Refer to your LDAP server documentation for how to create attributes and object classes, and set up the following. The following is LDIF data for ldapadd(1). Attribute and object class OIDs are examples only.

dn: cn=schema
changetype: modify
add: attributetypes
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.4.0 NAME 'nisplusEntryOwner' \
          DESC 'Opaque representation of NIS+ entry owner' \
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 SINGLE-VALUE )
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.4.1 NAME 'nisplusEntryGroup' \
          DESC 'Opaque representation of NIS+ entry group' \
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 SINGLE-VALUE )
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.4.2 NAME 'nisplusEntryAccess' \
          DESC 'Opaque representation of NIS+ entry access' \
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 SINGLE-VALUE )
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.4.3 NAME 'nisplusEntryTtl' \
          DESC 'Opaque representation of NIS+ entry TTL' \
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.26 SINGLE-VALUE )

dn: cn=schema
changetype: modify
add: objectclasses
objectclasses:  ( 1.3.6.1.4.1.42.2.27.5.42.42.5.0 NAME 'nisplusEntryData' \
          SUP top STRUCTURAL DESC 'NIS+ entry object non-column data' \
          MUST ( cn ) MAY ( nisplusEntryOwner $ nisplusEntryGroup $ \
          nisplusEntryAccess $ nisplusEntryTtl ) )

Edit the mapping file to enable storing entry owner, group, access, and TTL in LDAP. The template mapping file /var/nis/NIS+LDAPmapping.template has commented-out sections for the passwd and cred database ids that show how this can be done.

To preserve the cname and auth_name column data when cred.org_dir entries are stored in NIS+, you can create the nisplusPrincipalName and nisplusNetname attributes. See your LDAP server documentation for how to create attributes and object classes, and set up the following:

dn: cn=schema
changetype: modify
add: attributetypes
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.7.0 NAME 'nisplusPrincipalName' \
          DESC 'NIS+ principal name' \
          EQUALITY caseIgnoreIA5Match SINGLE-VALUE \
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.15 )
attributetypes: ( 1.3.6.1.4.1.42.2.27.5.42.42.9.0 NAME 'nisplusNetname' \
          DESC 'Secure RPC netname' \
          EQUALITY caseIgnoreIA5Match SINGLE-VALUE \
          SYNTAX 1.3.6.1.4.1.1466.115.121.1.15 )

dn: cn=schema
changetype: modify
add: objectclasses
objectclasses:  ( 1.3.6.1.4.1.42.2.27.5.42.42.10.0 NAME 'nisplusAuthName' \
          SUP top AUXILLIARY DESC 'NIS+ authentication identifiers' \
          MAY ( nisplusPrincipalName $ nisplusNetname ) )

Edit the mapping file to use the new nisplusPrincipalName and nisplusNetname. The template /var/nis/NIS+LDAPmapping file contains commented-out sections that support the nisplusPrincipalName and nisplusNetname attributes. See the nisplusLDAPobjectDN, nisplusLDAPattributeFromColumn and nisplusLDAPcolumnFromAttribute attribute values for the credlocal, creduser, and crednode database ids .

Attributes for Data Mapping

The following attributes are recognized. Any values specified for these attributes in the file, including an empty value, override values obtained from LDAP.

There are several attributes that can have multiple values, one for each database id. Depending on the source, the multiple values are specified in the following ways:

LDAP: Multi-valued attributes, where each value corresponds to one database id.
File: One line, which may be continued, for each value (database id). The line starts with the name of the attribute
Command: -x option for each value (database id).

Unless otherwise noted, all elements of the syntaxes below may be surrounded by white space. Separator characters and white space must be escaped if they are part of syntactic elements.

nisplusLDAPdatabaseIdMapping

Maps a database id to a NIS+ object. If the object name is not fully qualified, that is, it does not end in a dot, the nisplusLDAPbaseDomain is appended. See rpc.nisd(4). There is no default value. The syntax of the value is:

databaseId ":" objectspec

where

databaseId: Label identifying a subset of a NIS+ object for mapping purposes.
objectspec: objectname | "[" indexlist "]" tablename
objectname: The name of a NIS+ object (including tables)
tablename: The name of a NIS+ table
indexlist: colspec ["," colspec]
colspec: colname "=" colvalue
colname: The name of a column in the table
colvalue: colvaluestring | \" colvaluestring \"

The [indexlist]tablename form is intended for those cases where it is necessary to select a subset of a NIS+ table. The subset are those NIS+ entries that match the indexlist. If there are multiple indexed specifications for a particular NIS+ table, they are tried in the order retrieved until one matches. Note that retrieval order usually is unspecified for multi-valued LDAP attributes. Hence, if using indexed specifications when nisplusLDAPdatabaseIdMapping is retrieved from LDAP, make sure that the subset match is unambiguous.

If the colvaluestring contains white space or commas, it must either be surrounded by double quotes, or the special characters must be escaped.Wildcards are allowed in the colvaluestring. If the objectname or tablename is not fully qualified, the nisplusLDAPbaseDomain value is appended. If the objectname is empty the value of nisplusLDAPbaseDomain is substituted.

The following example shows how to associate the passwd database id with the passwd.org_dir table:

passwd:passwd.org_dir

The following example shows how to associate the LOCAL entries in the cred.org_dir table with the credlocal database id:

credlocal:[auth_type=LOCAL]cred.org_dir

The following example shows how to use the creduser database id for those entries in the cred.org_dir table that represent credentials (keys) for users. That is, they have a netname (auth_name) of the type unix.<numeric-id>@domain.

creduser:[auth_type="D*",auth_name="unix.[0-9]*"]cred.org_dir

nisplusLDAPentryTtl

Establish TTLs for NIS+ entries derived from LDAP. The syntax of the value is:

databaseId ":" initialTTLlo ":" initialTTLhi ":" runningTTL

initialTTLlo: The lower limit for the initial TTL (in seconds) for data read from disk when the rpc.nisd starts, or from LDAP during an initial down-load. See rpc.nisd(4) for the description of the nisplusLDAPinitialUpdate attribute. If initialTTLhi also is specified, the actual initialTTL will be randomly selected from the interval initialTTLlo to initialTTLhi, inclusive. If the field is left empty, it yields the default value of 1800 seconds.
initialTTLhi: The upper limit for the initial TTL. If left empty, it defaults to 5400.
runningTTL: The TTL (in seconds) for data retrieved from LDAP while the rpc.nisd is running. Leave the field empty to obtain the default value of 3600 seconds.

If there is no specification of TTLs for a particular databaseId, the default values are used. If the initialTTLlo and initialTTLhi have the same value, the effect will be that all data known to the rpc.nisd at startup times out at the same time. Depending on NIS+ data lookup patterns, this could cause spikes in rpc.nisd-to-LDAP traffic. In order to avoid that, you can specify different initialTTLlo and initialTTLhi values and obtain a spread in initial TTLs. The NIS+ object TTL is a separate and distinct entity used for other purposes, notably the TTL of NIS+ directory objects in the shared directory cache managed by the nis_cachemgr(1M). There is no connection between the nisplusLDAPentryTtl and object TTL values for a NIS+ object.

The following example shows how to specify that entries in the NIS+ hosts table read from LDAP should be valid for four hours. When the rpc.nisd restarts, the disk database entries are valid for between two and three hours.

hosts:7200:10800:14400

nisplusLDAPobjectDN

Specifies the connection between a databaseId and the LDAP directory. The syntax of the value is:

databaseId ":" objectDN *( ";" objectDN )

objectDN: readObjectSpec [":"[writeObjectSpec]]
readObjectSpec: [baseAndScope [filterAttrValList]]
writeObjectSpec: [baseAndScope [attrValList [":" deleteDisp]]]
baseAndScope: [baseDN] ["?" [scope]]
filterAttrValList: ["?" [filter | attrValList]]
scope: "base" | "one" | "sub"
attrValList: attribute "=" value *("," attribute "=" value)
deleteDisp: "always" | perDbId | "never"
perDbId: "dbid" "=" delDatabaseId
delDatabaseId: database id per nisplusLDAPdatabaseIdMapping above.

The baseDN defaults to the value of the defaultSearchBase attribute. If the baseDN ends in a comma, the defaultSearchBase is appended.

scope defaults to one. It has no meaning and is ignored in a writeObjectSpec. The filter is an LDAP search filter. There is no default value. The attrValList is a list of attribute and value pairs. There is no default value. As a convenience, if an attrValList is specified in a readObjectSpec, it is converted to a search filter by ANDing together the attributes and values. For example, the attribute and value list:

objectClass=posixAccount,objectClass=shadowAccount

is converted to the filter:

(&(objectClass=posixAccount)(objectClass=shadowAccount))

Entry objects are mapped by means of the relevant table mapping rules in the nisplusLDAPattributeFromColumn and nisplusLDAPcolumnFromAttribute attributes. Entry objects do not have explicit nisplusLDAPobjectDN attributes.

If a writeObjectSpec is omitted, and there is no trailing colon, the effect is to not attempt writes at all. If there is a trailing colon after the readObjectSpec, it is implied that the writeObjectSpec is the same as the readObjectSpec.

Note that writes only are attempted by a master server for the mapped NIS+ object. Replicas silently ignore any writeObjectSpec:s.

The deleteDisp specifies how NIS+ object deletion should be reflected in LDAP. The following values are recognized:

always: Always attempt to remove the LDAP entry. This is the default.
dbid=delDatabaseId: Set the mapped entries to values specified by the nisplusLDAPattributeFromColumn attribute values for delDatabaseId. This only makes sense for the databaseId:s corresponding to NIS+ tables or subsets of tables. For other NIS+ objects, if dbid= is specified, the action will be always. In the delDatabaseId, deletion of individual attributes can be specified by leaving the RHS of the = in a mapping rule empty. The delDatabaseId rule set should specify a dn. Otherwise, the rpc.nisd might try to derive a dn by performing an LDAP lookup on the attributes and values from the rule set, quite possibly with unexpected results.
never: Upon NIS+ object deletion, the corresponding LDAP data is left unchanged. If the NIS+ object is an entry, this means that the only effect of the deletion is to temporarily remove it from the rpc.nisd's cache.

The following is an example of how to get the ipnodes table entries from the ou=Hosts container under the default search base, and write to the same place.

ipnodes:ou=Hosts,?one?objectClass=ipHost:

The following example shows how to obtain the passwd table entries from the ou=People containers under the default search base, and also from dc=another,dc=domain. The latter is an example of the equivalent of and replacement for a NIS+ table path. Writes should only be attempted to the first objectDN. NIS+ entry deletions for the first objectDN are not reflected in LDAP:

passwd:ou=People,?one?objectClass=shadowAccount,\
                objectClass=posixAccount::never;\
        ou=People,dc=another,dc=domain,?one?\
                objectClass=shadowAccount,\
                objectClass=posixAccount

The following example shows how to obtain the passwd table entries from the ou=People container under the default search base. Upon NIS+ entry deletion, update the LDAP entry per the passwd_delete database id:

passwd:ou=People,?one?objectClass=shadowAccount,\
                objectClass=posixAccount::\
        dbid=passwd_delete

where nisplusLDAPattributeFromColumn for passwd_delete could be:

passwd_delete:\
        dn=("uid=%s,", name), \
        uid=name, \
        userPassword=("*NP*"), \
        uidNumber=uid, \
        gidNumber=gid, \
        gecos=("INVALID: %s", gcos), \
        homeDirectory=home, \
        loginShell=("/bin/false"), \
        (shadowLastChange,shadowMin,shadowMax, \
         shadowWarning, shadowInactive,shadowExpire, \
         shadowFlag)=(shadow, ":"), \
        nisplusEntryOwner=zo_owner, \
        nisplusEntryGroup=zo_group, \
        nisplusEntryAccess=zo_access

nisplusLDAPcolumnFromAttribute

Specifies how a NIS+ table and column value is derived from LDAP attribute values. The syntax is:

databaseId ":" colattrspec *("," colattrspec)

The format of colattrspec is shown below in the discussion of the column and attribute conversion syntax.

The following is an example of how to map by direct copy and assignment the value of the ipHostNumber attribute to the addr column:

addr=ipHostNumber

Formats for the column and attribute conversion syntax are discussed below, including examples of complex attribute to column conversions..

There are four special pseudo-columns that are used to indicate non-column entry object data:

zo_owner: The NIS+ principal that owns the entry object. By default, the zo_owner value is inherited from the table.
zo_group: The NIS+ group owner of the entry object. By default, the zo_group value is inherited from the table.
zo_access: The NIS+ access rights to the entry. Table column rights are stored in the table. By default, the zo_access value is inherited from the table.
zo_ttl: The NIS+ TTL for the entry. This is not the TTL for the entry when cached by the rpc.nisd. By default, the zo_ttl value is inherited from the table.

The default /var/nis/NIS+LDAPmapping.template assumes the existence of the following corresponding LDAP attributes in the containers for the passwd and cred tables:

nisplusEntryOwner
nisplusEntryGroup
nisplusEntryAccess
nisplusEntryTtl

These attributes are not part of any schema specified in an RFC or similar document. They must be created if they are to be used. They are assumed to belong to the as nisplusEntryData object class, and they contain a single string value. The format of this string is private, and subject to change without notice.

For most tables, the non-column entry data can be inherited from the containing table, and the pseudo-columns should be left unmapped. Notable exceptions are the passwd and cred tables, if individual users have access to modify their own passwd and cred entries. This would usually be the case if the site is not running the rpc.nispasswdd(1M) daemon.

nisplusLDAPattributeFromColumn

Specifies how an LDAP attribute value is derived from NIS+ table and column values. The syntax is:

databaseId ":" colattrspec *("," colattrspec )

The format of colattrspec is shown below in the discussion of the column and attribute conversion syntax.

As a special case, if the dn attribute value derived from a colattrspec ends in a comma (','), the baseDN from the writeObjectSpec is appended.

The following is an example of how to map the value of the addr column to the ipHostNumber attribute by direct copy and assignment:

ipHostNumber=addr

All relevant attributes, including the dn, must be specified. Non-column entry object data can be mapped as noted under the discussion of nisplusLDAPcolumnFromAttribute above.

Column and Attribute Conversion Syntax

The general format of a colattrspec is:

colattrspec     = lhs "=" rhs
lhs             = lval | namespeclist
rhs             = rval | [namespec]
namespeclist    = namespec | "(" namespec *("," namespec) ")"

The lval and rval syntax are defined below at Values. The format of a namespec is:

namespec: ["ldap:"] attrspec [searchTriple] | ["nis+:"] colspec [objectspec]
colspec: column | "(" column ")"
attrspec: attribute | "(" attribute ")"
searchTriple: ":" [baseDN] ["?" [scope] ["?" [filter]]]
baseDN: Base DN for search
filter: LDAP search filter
objectspec: objectspec per nisplusLDAPdatabaseIdMapping

The repository specification in a namespec defaults as follows:

For assignments to a column, nis+: on the LHS, ldap: on the RHS. NIS+ column values on the RHS are those that exist before the NIS+ entry is modified.
For assignments to an attribute, ldap: on the LHS, nis+: on the RHS. LDAP attribute values on the RHS are those that exist before the LDAP entry is modified.

Enclosing the column or attribute name in parenthesis denotes a list of column or attribute values. For attributes, the meaning is the list of all attributes of that name, and the interpretation depends on the context. See the discussion at Values. This list specification is ignored when a searchTriple or objectspec is supplied.

For columns, the (colname) syntax is used to map multiple attribute instances to multiple NIS+ entries.

The searchTriple can be used to specify an attribute from a location other than the read or write target. The defaults are as follows:

baseDN: If omitted, the default is the current objectDN. If the baseDN ends in a comma, the value of the defaultSearchBase attribute is appended.
scope: one
filter: Empty

Similarly, the objectspec can be used to specify a column value from a NIS+ table other than the one implicitly indicated by the databaseId. If searchTriple or objectspec is explicitly specified in a namespec, the retrieval or assignment, whether from or to LDAP or NIS+, is performed without checking if read and write are enabled for the LDAP container or NIS+ table.

Omitting the namespec in an rhs is only allowed if the lhs is one or more attributes. The effect is to delete the specified attribute(s). In all other situations, an omitted namespec means that the rule is ignored.

The filter can be a value. See Values. For example, to find the ipHostNumber using the cn, you could specify the following in the filter field:

ldap:ipHostNumber:?one?("cn=%s", (cname, "%s.*"))

In order to remove ambiguity, the unmodified value of a single column or attribute must be specified as the following when used in the filter field.

("%s", namespec)

If the filter is not specified, the scope will be base, and the baseDN is assumed to be the DN of the entry that contains the attribute to be retrieved or modified. To use previously existing column or attribute values in the mapping rules requires a lookup to find those values. Obviously, this will add to the time required to perform the modification. Also, there is a window between the time when a value is retrieved, and then slightly later, stored back. If the values have changed in the mean time, the change may be overwritten.

When colattrspecs are grouped into rule sets, in the value of a nisplusLDAPcolumnFromAttribute or nisplusLDAPattributeFromColumn attribute, the evaluation of the colattrspecs proceed in the listed order. However, evaluation may be done in parallel for multiple colattrspecs. If there is an error when evaluating a certain colattrspec, including retrieval or assignment of entry or column values, the extent to which the other colattrspec rules are evaluated is unspecified

Wildcards

Where wildcard support is available, it is of the following limited form:

*: Matches any number of characters.
[x]: Matches the character x.
[x-y]: Matches any character in the range x to y, inclusive..

Combinations such as [a-cA-C0123] are also allowed.This example would match any one of a, b, c, A, B, C, 0, 1, 2, or 3.

Substring Extraction

substringextract = "(" namespec "," matchspec ")"
name             = column or attribute name
matchspec        = \" formatstring \"

The matchspec is a string like the sscanf(3C) format string, except that there may be at most one format specifier, a single %s. The output value of the substringextract is the substring matching the location of the %s.

If there is no %s in the formatstring, it must instead be a single character, which is assumed to be a field separator for the namespec. The output values are the field values. Wild cards are supported. If there is no match, the output value is the empty string, "".

For example, if the column cname has the value user.some.domain.name., the value of the expression:

(cname, "%s.*")

is user, which can be used to extract the user name from a NIS+ principal name.

Similarly, use this expression to extract the third of the colon-separated fields of the shadow column:

(shadow, "*:*:%s:*")

This form can be used to extract all of the shadow fields. However, a simpler way to specify that special case is:

(shadow, ":")

Values

lval           = "(" formatspec "," namespec *("," namespec) ")" 
rval           = "(" formatspec ["," namelist ["," elide] ] ")"
namelist       = name_or_sse *( "," name_or_sse)
name_or_sse    = namespec | substringextract
formatspec     = \" formatstring \" 
formatstring   = A string combining text and % field specifications
elide          =\" singlechar \"
singlechar     = Any character

This syntax is used to produce rval values that incorporate column or attribute values, in a manner like sprintf(3C), or to perform assignments to lval like sscanf(3C). One important restriction is that the format specifications,% plus a single character, use the designations from ber_printf(3LDAP). Thus, while %s is used to extract a string value, %i causes BER conversion from an integer. Formats other than %s, for instance, %i, are only meaningfully defined in simple format strings without any other text.

The following ber_printf() format characters are recognized:

b  i  B  n  o  s

If there are too few format specifiers, the format string may be repeated as needed.

When used as an lval, there is a combination of pattern matching and assignment, possibly to multiple columns or attributes.

For example, in an assignment to an attribute, if the value of the addr column is 1.2.3.4, the rval:

("ipNetworkNumber=%s,", addr)

produces the value ipNetworkNumber=1.2.3.4,, while:

("(%s,%s,%s)", host, user, domain)

results in (assuming host="xyzzy", user="-", domain="x.y.z") "(xyzzy,-,x.y.z)". The elide character feature is used with attribute lists. For example:

("%s,", (mgrprfc822mailmember), ",")

concatenates all mgrprfc822mailmember values into one comma-separated string, and then elides the final trailing comma. Thus, for

mgrprfc822mailmember=usera
mgrprfc822mailmember=userb        
mgrprfc822mailmember=userc

the value would be usera,userb,userc.

If the NIS+ column intval is in binary format, that is, the B column flag is set, and it is to be interpreted as an integer, the following:

("%i", intval)

produces a value suitable for assignment to an integer-valued attribute.

The nisPublicKey attribute encodes the algorithm type and number (equivalent to the auth_type column) and the public key as a single string such as {dh192-0}xxxxxxxx (public key truncated for clarity). The following will extract the corresponding auth_type and public_data values:

("{%s}%s", auth_type, public_data)

As a special case, to combine an LHS extraction with an RHS implicit list creates multiple entries and values. For example,

("(%s,%s,%s)", host, user, domain)=(nisNetgroupTriple)

creates one NIS+ entry for each nisNetgroupTriple value.

Assignments

The assignment syntax, also found at Column and Attribute Conversion Syntax , is as follows:

colattrspec    = lhs "=" rhs
lhs            = lval | namespeclist
rhs            = rval | namespec
namespeclist   = namespec | "(" namespec *("," namespec) ")"

By using the syntax defined above, the general form of a simple assignment, which is a one-to-one mapping of column to attribute, would be:

("%s", colname)=("%s", attrname)

As a convenient short-hand, this can also be written as:

colname=attrname

A list specification, which is a name enclosed in parenthesis, can be used to make many-to-many assignments. The expression:

(colname)=(attrname)

where there are multiple instances of attrname, creates one NIS+ entry for each such instance, differentiated by their colname values. The following combinations of lists are allowed, but they are not particularly useful:

(attrname)=(colname): Equivalent to attrname=colname
attrname=(colname): Equivalent to attrname=colname
(colname)=attrname: Equivalent to colname=attrname
colname=(attrname): Equivalent to colname=attrname

If a multi-valued RHS is assigned to a single-valued LHS, the LHS value will be the first of the RHS values. If the RHS is an attribute list, the first attribute is the first one returned by the LDAP server when queried. Otherwise, the definition of “first” is implementation dependent.

Finally, the LHS might be an explicit list of columns or attributes, such as:

(name1,name2,name3)

If the RHS is single-valued, this assigns the RHS value to all entities in the list. If the RHS is multi-valued, the first value is assigned to the first entity of the list, the second value to the second entity, and so on. Excess values or entities are silently ignored.

EXAMPLES

Example 1 Assigning an Attribute Value to a Column

The following example illustrates how to assign the value of the ipHostNumber attribute to the addr column

addr=ipHostNumber

Example 2 Creating Multiple NIS+ Entries from Multi-Valued LDAP Attributes

An LDAP entry with:

cn=name1
cn=name2        
cn=name3

and the following assignments:

cname=cn
(name)=(cn

creates three NIS+ entries (other attributes/columns omitted for clarity):

cname=name1, name=name1
cname=name1, name=name2
cname=name1, name=name3

Example 3 Assigning String Constants

The following expression sets the auth_type column to LOCAL:

auth_type=("LOCAL")

Example 4 Splitting Column Values to Multi-Valued Attributes

The expansion column contains a comma-separated list of alias member names. In the following example, the expression assigns each such member name to an instance of mgrprfc822mailmember:

(mgrprfc822mailmember)=(expansion, ",")

Example 5 Splitting Column Values to Multiple Attributes

The shadow column contains a colon-separated list of fields. The following assigns the value of the first field to shadowLastChange, the value of the second field to shadowMin, and so forth.

(shadowLastChange,shadowMin,shadowMax,shadowWarning,\
       shadowInactive,shadowExpire,shadowFlag)=(shadow, ":")

FILES

/var/nis/NIS+LDAPmapping: Default mapping file used by rpc.nisd(1M).
/var/nis/NIS+LDAPmapping.template: Template file covering the standard NIS+ directories and tables.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Availability	SUNWnisr
Interface Stability	Obsolete

NOTES

RFC 2307bis is an IETF informational document in draft stage that defines an approach for using LDAP as a naming service.

SunOS 5.9 Last Revised 12 Jun 2002