When "setenv PUSH_PEER_INFO" or "push-peer-info" is present
in client config, push the MAC address of the interface
owning the default route to the server via IV_HWADDR.
Triple DES, and other 64-bit block-size ciphers vulnerable
to "Sweet32" birthday attack (CVE-2016-6329). Limit such
cipher keys to no more than 64 MB of data
encrypted/decrypted. While our overall goal is to limit
data-limited keys to 64 MB, we trigger a renegotiation
at 48 MB to compensate for possible delays in renegotiation
and rollover to the new key.
This client-side implementation extends data limit
protection to the entire session, even when the server
doesn't implement data limits.
This capability is advertised to servers via the a
peer info setting:
IV_BS64DL=1
meaning "Block-Size 64-bit Data Limit". The "1" indicates
the implementation version.
The implementation currently has some limitations:
* Keys are renegotiated at a maximum rate of once per
5 seconds to reduce the likelihood of loss of
synchronization between peers.
* The maximum renegotiation rate may be further extended
if the peer delays rollover from the old to new key
after renegotiation.
Added N_KEY_LIMIT_RENEG stats counter to count the number
of data-limit-triggered renegotiations.
Added new stats counter KEY_STATE_ERROR which roughly
corresponds to the OpenVPN 2.x error "TLS Error:
local/remote TLS keys are out of sync".
Prevously, the TLS ack/retransmit timeout was hardcoded to
2 seconds. Now we lower the default to 1 second and make
it variable using the (pushable) "tls-timeout" directive.
Additionally, the tls-timeout directive can be specified
in milliseconds instead of seconds by using the
"tls-timeout-ms" form of the directive.
Made the "become primary" time duration configurable via
the (pushable) "become-primary" directive which accepts
a number-of-seconds parameter. become-primary indicates
the time delay between renegotiation and rollover to the
new key for encryption/transmission. become-primary
defaults to the handshake-window which in turn defaults
to 60 seconds.
Incremented core version to 3.0.20.
near Connected event to fire one second after Connected
event, to reduce the chance of race conditions in the client
app, if the INFO event triggers the client app to perform an
operation that requires the VPN tunnel to be ready.
a DNS lookup. This requires that RemoteList now owns a
RandomAPI::Ptr, which in turn simplifies the signature of
some other RemoteList methods such as randomize().
could occur even if tun_persist is disabled.
In particular, we now consider a set of multiple IP
addresses returned by a single DNS lookup to constitute a
kind of cache. This helps us to not get stuck on stale
addresses when transitioning between NAT64 and regular
networks.
