Endpoint Message Authentication for AODV Route MessagesFuturewei Inc. 2330 Central ExpresswaySanta Clara95050CAUSA+1-408-330-4586charliep@computer.org
Routing
Mobile Ad Hoc Networks [manet]MobilityE2E security
This document specifies a new type extension to enable RFC 7182
authentication mechanism to be used for authenticating AODVv2 route
messages. The document also specifies a new message TLV for AODVv2
and, potentially,
other reactive protocols. Both mechanisms allow the endpoints of
a newly discovered route to be assured that they were the originator of
the RREQ and responder producing the RREP respectively.
In certain cases during route discovery, it would be useful for the
source and destination nodes for the discovered routes to verify
each others' participation in the route discovery process, and thus that
a route was indeed established between them. This does not guarantee
a functioning route because malicious intermediate
nodes might still misdirect or drop traffic.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL
NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED",
"MAY", and "OPTIONAL" in this document are to be interpreted as
described in . This document also uses some terminology from
, and
AODVv2 .
For the computations specified in this document, the input data
(i.e., content) is the the concatenation of the following data
contained in the AODVv2 message,
in this order:
OrigAddr TargAddr PrefixLengthList if present in the message OrigSeqNum if present in the message TargSeqNum if present in the message MetricType
The authentication algorithm uses a new type extension to
allow AODVv2 to compute the ICV-data on the selected input data.
In order to conform to the
specification within RFC 7182 for a new
type extension, this document specifies the following details.
The input data for the computation is as specified in
, padded up to the nearest multiple of 16 bytes.
The output of the computation is truncated to a 128-bit authenticator
value which is used for the ICV-data field of the ICV Message TLV.
Every AODVv2 conforming to this specification MUST support AES-CMAC
as the cryptographic algorithm.
The authentication algorithm uses HMAC-SHA-256-128
to compute authentication data.
The output of the computation is a 128-bit authenticator value which
is used for the value field of the E2E Message TLV ICV-data.
The format for the E2E Message TLV ICV-data is shown in
.
The E2E Message TLV ICV-data typeMUST be transmitted as zero
and ignored on reception.128 bits authentication data
computed as described in .
This document introduces a security mechanism to enable
the two endpoints of a route discovery operation to verify that
they are using the same immutable data elements as were supplied
by the node generating the Route Discovery message (i.e., RREQ or RREP).
This allows rejection of malicious false routes for OrigAddr or
TargAddr of AODVv2 route discovery operations.
This document specifies the designation of a new type extension
to be allocated from the "ICV Message TLV Type Extensions" registry
defined in . The specification for the
use of the new type extension is contained in
.
For the Message TLV ICV-data TLV, this document specifies the
designation of a new Message TLV Type to be allocated from the
"Message TLV Types" namespace defined in .
This document has benefitted from comments by Vicky Mercieca and
from other discussion with the AODVv2 author team.