diff options
Diffstat (limited to 'raddb/policy.d/dhcp')
| -rw-r--r-- | raddb/policy.d/dhcp | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/raddb/policy.d/dhcp b/raddb/policy.d/dhcp new file mode 100644 index 0000000..1752acb --- /dev/null +++ b/raddb/policy.d/dhcp @@ -0,0 +1,327 @@ +# Assign common DHCP reply packet options +dhcp_common { + # The contents here are invented. Change them! + update reply { + &DHCP-Domain-Name-Server = 127.0.0.1 + &DHCP-Domain-Name-Server += 127.0.0.2 + &DHCP-Subnet-Mask = 255.255.255.0 + &DHCP-Router-Address = 192.0.2.1 + &DHCP-Broadcast-Address = 192.0.2.255 + &DHCP-IP-Address-Lease-Time = 7200 + &DHCP-DHCP-Server-Identifier = &control:DHCP-DHCP-Server-Identifier + } +} + +# Lookup DHCP group based options. This policy allows for membership +# of multiple groups so can cover the ISC concepts of "group" and "class" +# To use this enable the "dhcp_files" module +#dhcp_group_options { +# foreach &request:DHCP-Group-Name { +# dhcp_set_group_options +# } +#} + +# Policy to override DHCP-Network-Subnet +# +# Some networks have a "shared-network" or "multinet" configuration (as +# defined by some other DHCP servers) in which multiple IP subnets may +# co-exist in a single Layer 2 network (or VLAN). +# +# In enterprise environments this is often for the purpose of providing loose +# segregation between classes of devices such as local network-attached +# storage or IP telephony. There are valid reasons why each of the subnets is +# not seperately VLANed, such as to enable the use of ICMP redirects to avoid +# hairpinning of cross-subnet traffic via a gateway. +# +# In ISP environments this is a common configuration for edge networks whose +# access is provided by DOCSIS cable modems that share a VLAN with the devices +# they provide a service to but are seperately addressed. +# +# Where it is necessary to force the selection of a particular subnet for a +# device, multiple pools must be configured for each subnet and referenced +# with unique identifiers in the *network-specific* section of +# mods-config/files/dhcp. +# +# By default DHCP-Network-Subnet is populated such that it normally +# refers to the Layer 2 network from which the DHCP query originates - we +# cannot know the intended subnet for the device without additional input to +# the policy. +# +# Override DHCP-Network-Subnet to be an address within the desired +# network to force selection of a particular address pool and/or network +# parameters. +# +# Note: If each subnet within a network is equally valid for the DHCP requests +# originating from that network then you do not need to call this policy, +# rather look at the examples concerning dhcp_subnet in +# mods-config/files/dhcp instead, which use a single pool containing addresses +# from all subnets then set the correct subnet-specific options based on the +# randomly assigned IP address. +# +#dhcp_override_network { +# if (&DHCP-Vendor-Class-Identifier && &DHCP-Vendor-Class-Identifier == "SIP100") +# update request { +# DHCP-Network-Subnet := 10.10.0.0 +# } +# } +#} + + +# Policy that calls the files instance of the same name after first making +# DHCP-Network-Subnet specific to the allocated IP address of the client. +#dhcp_subnet { +# update { +# &DHCP-Network-Subnet := "%{%{reply:DHCP-Your-IP-Address}:-%{DHCP-Client-IP-Address}}" +# } +# +# # Call the dhcp_subnet instance of the files module +# dhcp_subnet +#} + +# Assign compatibility data to request for sqlippool for DHCP Request +dhcp_sqlippool_request { + + # + # During initial address selection (DORA) the REQUEST is broadcast and + # requested-ip must be provided. We revoke any active offers for addresses + # not matching the requested-ip, i.e. those made by other servers when + # processing the DISCOVER. + # + # If there is only a single server then this optimisation can be disabled. + # + if (&DHCP-Requested-IP-Address) { + update request { + &Acct-Status-Type := Start + } + dhcp_sqlippool.accounting + } + + # Extend an existing offer or active lease + update request { + &Acct-Status-Type := Alive + } + dhcp_sqlippool.accounting { + notfound = return + } + + update reply { + &DHCP-Your-IP-Address := "%{%{DHCP-Requested-IP-Address}:-%{DHCP-Client-IP-Address}}" + } + +} + +# Assign compatibility data to request for sqlippool for DHCP Release +dhcp_sqlippool_release { + + # Do some minor hacks to the request so that it looks + # like a RADIUS Accounting Stop request to the SQL IP Pool module. + update request { + &Acct-Status-Type = Stop + } + + # Call the actual module in accounting context + dhcp_sqlippool.accounting + +} + +# Assign compatibility data to request for sqlippool for DHCP Decline +dhcp_sqlippool_decline { + + # Do a minor hack to the request so that it looks + # like a RADIUS Accounting Off request to the SQL IP Pool module. + update request { + &Acct-Status-Type = Accounting-Off + } + + # Call the actual module in accounting context + dhcp_sqlippool.accounting + +} + +# Example policy for fetching option data from SQL +dhcp_policy_sql { + + # + # Network-specific options + # + + # + # We want to lookup the Layer 2 network specific DHCP options to + # include in the reply. For this we need a stable identifier for the + # network from which the request is originating (based on + # DHCP-Network-Subnet) which can be used as the lookup key + # (DHCP-SQL-Option-Identifier) for the network options. + # + # Here we fabricate an example for the purpose of placing all + # configuration elements into SQL. We use a PostgreSQL query that + # returns the network identifier in the row containing the smallest + # enclosing CIDR, which assumes a schema such as the following: + # + # CREATE TABLE fr_network_to_identifier (network CIDR, network_id TEXT) + # + # Note: An rlm_files based lookup of the network_identifier (as per + # the examples in the dhcp virtual server) may be preferable to an ad + # hoc SQL query assuming that the network topology does not change + # frequently. + # +# update control { +# &control:Tmp-String-0 := "%{dhcp_sql:SELECT network_id \ +# FROM fr_network_to_identifier \ +# WHERE '%{DHCP-Network-Subnet}'::inet << network \ +# ORDER BY MASKLEN(network) DESC LIMIT 1;}" +# } + + # + # Use the network identifer to lookup the options specific to the + # originating network, using "network" context. Common network + # settings can be placed into a group and shared, with individual + # networks mapped to one or more option groups. + # + # - Place network-specific options in the dhcpreply table with + # "context = 'network'". + # - Add "Fall-Through := Yes" to the network options in the dhcpreply + # table to trigger group lookups for the network, which are + # disabled by default. + # - Place "identifier = <network_id>, groupname = <group>, + # priority = <priority>, context = 'network'" in the dhcpgroup + # table to map a network to a shared set of network options. + # - Place group-specific options in the dhcpgroupreply table with + # "context = 'network'". + # + # Note: In "shared-network" or "multinet" topologies you can instead + # just set all of the network options once in the subnet-specific + # options (after obtaining an IP address), below. + # +# update control { +# &DHCP-SQL-Option-Context := "network" +# &DHCP-SQL-Option-Identifier := &control:Tmp-String-0 +# } +# dhcp_sql.authorize + + + # + # Allocate IPs from the DHCP pool in SQL. + # + # Here we simply reuse the network_id (obtained previously) as the + # Pool-Name. + # +# update control { +# &Pool-Name := &control:Tmp-String-0 +# } +# dhcp_sqlippool + + + # + # Subnet-specific options + # + + # + # In "shared-network" or "multinet" topologies (in which a Layer 2 + # network has a single pool that contains addresses from multiple + # subnets) it is necessary to set subnet-specific options based on the + # address that has just been allocated. + # + # Again, for this we need to derive a stable identifier for the subnet + # to which the IP address we are issuing belongs that will serve as a + # lookup key for the network options. + # + # Continuing our previous example, we can use a PostgreSQL query to + # find the subnet identifer in the row with the closest enclosing + # CIDR, which assumes a schema such as the following: + # + # CREATE TABLE fr_subnet_to_identifier (subnet CIDR, subnet_id TEXT) + # + # Note: An rlm_files based lookup of the subnet_identifier (as per the + # examples in the dhcp virtual server) is preferable to an ad hoc SQL + # query assuming that the network topology does not change frequently. + # +# update control { +# &control:Tmp-String-0 := "%{dhcp_sql:SELECT subnet_id \ +# FROM fr_subnet_to_identifier \ +# WHERE '%{reply:DHCP-Your-IP-Address}'::inet << subnet \ +# ORDER BY MASKLEN(subnet) DESC LIMIT 1;}" +# } + + # + # Use the subnet identifer to lookup the options specific to the + # subnet for the IP we are allocating, using "subnet" context. Common + # subnet settings can be placed into a group and shared, with + # individual subnets mapped to one or more option groups. + # + # - Place subnet-specific options in the dhcpreply table with + # "context = 'subnet'". + # - Add "Fall-Through := Yes" to the subnet options in the dhcpreply + # table to trigger group lookups for the subnet, which are + # disabled by default. + # - Place "identifier = <subnet_id>, groupname = <group>, + # priority = <priority>, context = 'subnet'" in the dhcpgroup + # table to map a subnet to a shared set of subnet options. + # - Place group-specific options in the dhcpgroupreply table with + # "context = 'subnet'". + # +# update control { +# &DHCP-SQL-Option-Context := "subnet" +# &DHCP-SQL-Option-Identifier := &control:Tmp-String-0 +# } +# dhcp_sql.authorize + + + # + # Host-specific and group-specific options + # + + # "Groups" conventionally differentiate devices based on manual + # groupings using a device-specific identifier such as the MAC + # address. + # + # - Place host-specific options in the dhcpreply table with + # "context = 'group'". + # - Add "Fall-Through := Yes" to the device options in the dhcpreply + # table to trigger group lookups, which are disabled by default. + # - Place "identifier = <MAC-Address>, groupname = <group>, + # priority = <priority>, context='group'" in the dhcpgroup table + # to map a device to its groups. + # - Place group-specific options in the dhcpgroupreply table with + # "context = 'group'". + # +# update control { +# &DHCP-SQL-Option-Context := "group" +# &DHCP-SQL-Option-Identifier := &request:DHCP-Client-Hardware-Address +# } +# dhcp_sql.authorize + + + # + # Class/subclass-specific options + # + + # + # "Classes" conventionally differentiate devices based on all or part + # of one or more DHCP request options, or any combination of + # information that is available in the request or has already looked + # up from some datastore. + # + # Create multiple instances of the following block, one for each + # class. Differentiate between classes by setting + # DHCP-SQL-Option-Context uniquely. + # + # - Place "subclass"-specific options (i.e. each member of a class) + # in the dhcpreply table with "context = <class-name>". + # - For class-level options common to every member of a class, + # either: + # - Duplicate the options for each member of the subclass. + # or: + # - Add "Fall-Through := Yes" to each members options to trigger + # group lookups, which are disabled by default. + # - Map each member of the class to a group in the dhcpgroup + # table with context = '<class-name>'; + # - Create the corresponding class in the dhcpgroupreply table + # with "context = '<class-name>'". + # +# update control { +# &DHCP-SQL-Option-Context := "class-vci-substring" +# &DHCP-SQL-Option-Identifier := "%{substring %{request:DHCP-Vendor-Class-Identifier} 5 4}" +# } +# dhcp_sql.authorize + +} |