Version 2.4.0
=============


New features
------------

pull-filter
    New option to explicitly allow or reject options pushed by the server.
    May be used multiple times and is applied in the order specified.

push-remove
    new option to remove options on a per-client basis from the "push" list
    (more fine-grained than "push-reset")

keying-material-exporter
    Keying Material Exporter [RFC-5705] allow additional keying material to be
    derived from existing TLS channel.

redirect-gateway ipv6
    OpenVPN has now feature parity between IPv4 and IPv6 for redirect
    gateway including the handling of overlapping IPv6 routes with
    IPv6 remote VPN server address

Mac OS X Keychain management client
    add contrib/keychain-mcd which allows to use Mac OS X keychain
    certificates with OpenVPN

Peer ID support
    Added new packet format P_DATA_V2, which includes peer-id. If
    server and client  support it, client sends all data packets in
    the new format. When data packet arrives, server identifies peer
    by peer-id. If peer's ip/port has changed, server assumes that
    client has floated, verifies HMAC and updates ip/port in internal structs.

Dualstack client connect
    Instead of only using the first address of each --remote OpenVPN
    will now try all addresses (IPv6 and IPv4) of a --remote entry.

LZ4 Compression
    Additionally to LZO compression OpenVPN now also supports LZ4
    compression.

Windows version
    Windows version is detected, logged and possibly signalled to server
    (IV_PLAT_VER=<nn> if --push-peer-info is set on client)

AEAD (GCM) data channel cipher support
    The data channel now supports AEAD ciphers (currently only GCM).  The AEAD
    packet format has a smaller overhead than the CBC packet format, (e.g. 20
    bytes per packet for AES-128-GCM instead of 36 bytes per packet for
    AES-128-CBC + HMAC-SHA1).

Http proxy password inside config file
	Http proxy passwords can be specified with the inline file option
    http-proxy-user-pass


User-visible Changes
--------------------
- For certificate DNs with duplicate fields, e.g. "OU=one,OU=two", both fields
  are now exported to the environment, where each second and later occurrence
  of a field get _$N appended to it's field name, starting at N=1.  For the
  example above, that would result in e.g. X509_0_OU=one, X509_0_OU_1=two.
  Note that this breaks setups that rely on the fact that OpenVPN would
  previously (incorrectly) only export the last occurence of a field.

- proto udp and proto tcp specify to use IPv4 and IPv6. The new
  options proto udp4 and tcp4 specify to use IPv4 only.

- connect-timeout specifies now the timeout until the first TLS packet
  is received (identical to server-poll-timeout) and this timeout now
  includes the removed socks proxy timeout and http proxy timeout.

  In --static mode connect-timeout specifies the timeout for TCP and
  proxy connection establishment

- connect-retry-max now specifies the maximum number of unsuccessful
  attempts of each remote/connection entry before exiting.

- sndbuf and recvbuf default now to OS default instead of 64k

- OpenVPN exits with  an error if an option has extra parameters;
  previously they were silently ignored

- The default of tls-cipher is now "DEFAULT:!EXP:!PSK:!SRP:!kRSA"
  instead of "DEFAULT" to always select perfect forward security
  cipher suites

- --tls-auth always requires OpenVPN static key files and will no
  longer work with free form files

- proto udp6/tcp6 in server mode will now try to always listen to
  both IPv4 and IPv6 on platforms that allow it. Use bind ipv6only
  to explicitly listen only on IPv6.

- Removed --enable-password-save from configure. This option is now
  always enabled.

- Stricter default TLS cipher list (override with ``--tls-cipher``), that now
  also disables:

  * Non-ephemeral key exchange using static (EC)DH keys
  * DSS private keys

- mbed TLS builds: changed the tls_digest_N values exported to the script
  environment to be equal to the ones exported by OpenSSL builds, namely
  the certificate fingerprint (was the hash of the 'to be signed' data).

- mbed TLS builds: minimum RSA key size is now 2048 bits.  Shorter keys will
  not be accepted, both local and from the peer.

- --http-proxy-timeout and the static non-changeable socks timeout (5s)
  have been folded into a "unified" --connect-timeout which covers all
  steps needed to connect to the server, up to the start of the TLS exchange.
  The default value has been raised to 120s, to handle slow http/socks
  proxies graciously.  The old "fail TCP fast" behaviour can be achieved by
  adding "--connect-timeout 10" to the client config.

- --http-proxy-retry and --sock-proxy-retry have been removed. Proxy connections
    will now behave like regular connection entries and generate a USR1 on failure.

- --connect-retry gets an optional second argument that specifies the maximum
  time in seconds to wait between reconnection attempts when an exponential
  backoff is triggered due to repeated retries. Default = 300 seconds.

Maintainer-visible changes
--------------------------
- OpenVPN no longer supports building with crypto support, but without TLS
  support.  As a consequence, OPENSSL_CRYPTO_{CFLAGS,LIBS} and
  OPENSSL_SSL_{CFLAGS,LIBS} have been merged into OPENSSL_{CFLAGS,LIBS}.  This
  is particularly relevant for maintainers who build their own OpenSSL library,
  e.g. when cross-compiling.