[govpn.git] / doc / news.texi

@node News
@unnumbered News

See also this page @ref{Новости, on russian}.

@node Release 7.4
@section Release 7.4
@itemize
@item Tiny refactoring. Go 1.9 is minimal required version.
@item Dependant cryptographic libraries are updated.
@end itemize

@node Release 7.3
@section Release 7.3
@itemize
@item Fixed seldom possible segmentation fault on the server during
rehandshake.
@item Dependant cryptographic libraries are updated.
@end itemize

@node Release 7.2
@section Release 7.2
@itemize
@item Fixed fatal bug in nonce generation code, appeared in 7.1 version.
Everyone @strong{have to} update.
@end itemize

@node Release 7.1
@section Release 7.1
@itemize
@item Fixed bug in client's identity generation and detection code:
simultaneous clients may be incorrectly identified, preventing their
connection establishing and allowing DPI to detect GoVPN packets.
@end itemize

@node Release 7.0
@section Release 7.0
@itemize
@item (X)Salsa20 is replaced with ChaCha20. Theoretically it should be
faster and more secure. Previous versions are not compatible with it!
@item Ability to use TUN-interfaces under GNU/Linux. FreeBSD has already
supported them without any modifications.
@end itemize

@node Release 6.0
@section Release 6.0
@itemize
@item Argon2d is replaced with Balloon hashing. Found Argon2 libraries
written on pure Go have various problems. Moreover Argon2i should be
used instead, but it has some possible
@url{http://eprint.iacr.org/2016/027, cryptographic defects}. So it is
replaced with much more simpler (and seems even cryptographically
better) @url{https://crypto.stanford.edu/balloon/, Balloon hashing}.
@end itemize

@node Release 5.10
@section Release 5.10
@itemize
@item @option{-version} option added, printing program version.
@end itemize

@node Release 5.9
@section Release 5.9
@itemize
@item Client reconnects in the loop when connection is lost. Optionally
you can disable that behaviour: client will exit immediately, as it
previously did.
@end itemize

@node Release 5.8
@section Release 5.8
@itemize
@item Optional ability to use syslog for logging, with
@url{https://tools.ietf.org/html/rfc5424, RFC 5424}-like
structured records.
@item XTEA algorithm is not used anymore for nonce obfuscation, but
BLAKE2b-MAC instead. Encryptionless mode now really does not depend on
encryption functions.
@end itemize

@node Release 5.7
@section Release 5.7
@itemize
@item TAP interface name and remote peer's address are passed to up- and
down- scripts through environment variables.
@item Update Argon2 library to use version 1.3 of the algorithm.
@end itemize

@node Release 5.6
@section Release 5.6
@itemize
@item Added up/down example script for replacing default route (thanks
to Zhuoyun Wei).
@item Fixed documentation bug: @file{.info} was not installing.
@end itemize

@node Release 5.5
@section Release 5.5
@itemize
@item Ability to work on 32-bit platforms. @emph{sync/atomic} library
has some specific issues that caused panics on previous versions.
@end itemize

@node Release 5.4
@section Release 5.4
@itemize
@item Added optional time synchronization requirement.
It will add timestamps in handshake PRP authentication, disallowing to
repeat captured packet and get reply from the server, making it visible
to DPI.
@end itemize

@node Release 5.3
@section Release 5.3
@itemize
@item Fixed minor bug with @command{newclient.sh} that caught
"Passphrase:" prompt and inserted it into example YAML output.
Just replaced stdout output to stderr for that prompt.
@end itemize

@node Release 5.2
@section Release 5.2
@itemize
@item Ability to read passphrases directly from the terminal (user's
input) without using of keyfiles. @command{storekey.sh} utility removed.
@end itemize

@node Release 5.1
@section Release 5.1
@itemize
@item Server is configured using @url{http://yaml.org/, YAML} file. It
is very convenient to have comments and templates, comparing to JSON.
@item Incompatible with previous versions replacement of @emph{HSalsa20}
with @emph{BLAKE2b} in handshake code.
@end itemize

@node Release 5.0
@section Release 5.0
@itemize
@item New optional encryptionless mode of operation.
Technically no encryption functions are applied for outgoing packets, so
you can not be forced to reveal your encryption keys or sued for
encryption usage.
@item MTUs are configured on per-user basis.
@item Simplified payload padding scheme, saving one byte of data.
@item Ability to specify TAP interface name explicitly without any
up-scripts for convenience.
@item @command{govpn-verifier} utility also can use EGD.
@end itemize

@node Release 4.2
@section Release 4.2
@itemize
@item Fixed non-critical bug when server may fail if up-script is not
executed successfully.
@end itemize

@node Release 4.1
@section Release 4.1
@itemize
@item @url{https://password-hashing.net/#argon2, Argon2d} is used instead
of PBKDF2 for password verifier hashing.
@item Client's identity is stored inside the verifier, so it simplifies
server-side configuration and the code.
@end itemize

@node Release 4.0
@section Release 4.0
@itemize
@item Handshake messages can be noised: their messages lengths are
hidden. Now they are indistinguishable from transport messages.
@item Parallelized clients processing on the server side.
@item Much higher overall performance.
@item Single JSON file server configuration.
@end itemize

@node Release 3.5
@section Release 3.5
@itemize
@item Ability to use TCP network transport.
Server can listen on both UDP and TCP sockets.
@item Ability to use HTTP proxies (through CONNECT method)
for accessing the server. Server can also emulate HTTP proxy behaviour.
@item Updated Poly1305 library with ARM-related bugfixes.
@item Go 1.5+ version is highly recommended because of performance
reasons.
@end itemize

@node Release 3.4
@section Release 3.4
@itemize
@item Ability to use external EGD-compatible PRNGs. Now you are
able to use GoVPN even on systems with the bad @file{/dev/random},
providing higher quality entropy from external sources.
@item Removed @option{-noncediff} option. It is replaced with in-memory
storage of seen nonces, thus eliminating possible replay attacks at all
without performance degradation related to inbound packets reordering.
@end itemize

@node Release 3.3
@section Release 3.3
@itemize
@item Compatibility with an old GNU Make 3.x. Previously only BSD Make
and GNU Make 4.x were supported.
@item @file{/dev/urandom} is used for correct client identity generation
under GNU/Linux systems. Previously @file{/dev/random} can produce less
than required 128-bits of random.
@end itemize

@node Release 3.2
@section Release 3.2
@itemize
@item Deterministic building: dependent libraries source code commits
are fixed in our makefiles.
@item No Internet connection is needed for building the source code: all
required libraries are included in release tarballs.
@item FreeBSD Make compatibility. GNU Make is not necessary anymore.
@end itemize

@node Release 3.1
@section Release 3.1
@itemize
@item
Diffie-Hellman public keys are encoded with Elligator algorithm when
sending over the wire, making them indistinguishable from the random
strings, preventing detection of successful decryption try when guessing
passwords (that are used to create DSA public keys). But this will
consume twice entropy for DH key generation in average.
@end itemize

@node Release 3.0
@section Release 3.0
@itemize
@item
EKE protocol is replaced by Augmented-EKE and static symmetric (both
sides have it) pre-shared key replaced with server-side verifier. This
requires, 64 more bytes in handshake traffic, Ed25519 dependency with
corresponding sign/verify computations, PBKDF2 dependency and its
usage on the client side during handshake.

A-EKE with PBKDF2-based verifiers is resistant to dictionary attacks,
can use human memorable passphrases instead of static keys and
server-side verifiers can not be used for authentication (compromised
server does not leak client's authentication keys/passphrases).

@item
Changed transport message structure: added payload packet's length.
This will increase transport overhead for two bytes, but heartbeat
packets became smaller

@item
Ability to hide underlying packets lengths by appending noise, junk
data during transmission. Each packet can be fill up-ed to its
maximal MTU size.

@item
Ability to hide underlying packets appearance rate, by generating
Constant Packet Rate traffic. This includes noise generation too.
@item
Per-peer @option{-timeout}, @option{-noncediff}, @option{-noise} and
@option{-cpr} configuration options for server.
@end itemize

@node Release 2.4
@section Release 2.4
@itemize
@item Added ability to optionally run built-in HTTP-server responding
with JSON of all known connected peers information. Real-time client's
statistics.
@item Documentation is explicitly licenced under GNU FDL 1.3+.
@end itemize

@node Release 2.3
@section Release 2.3
@itemize
@item Handshake packets became indistinguishable from the random. Now
all GoVPN's traffic is the noise for men in the middle.

@item Handshake messages are smaller (16% traffic reduce).

@item Adversary now can not create malicious fake handshake packets that
will force server to generate private DH key, preventing entropy
consuming and resource heavy computations.
@end itemize

@node Release 2.2
@section Release 2.2
@itemize
@item Fixed several possible channel deadlocks.
@end itemize

@node Release 2.1
@section Release 2.1
@itemize
@item Fixed Linux-related building.
@end itemize

@node Release 2.0
@section Release 2.0
@itemize
@item Added clients identification.
@item Simultaneous several clients support by server.
@item Per-client up/down scripts.
@end itemize

@node Release 1.5
@section Release 1.5
@itemize
@item Nonce obfuscation/encryption.
@end itemize

@node Release 1.4
@section Release 1.4
@itemize
@item Performance optimizations.
@end itemize

@node Release 1.3
@section Release 1.3
@itemize
@item Heartbeat feature.
@item Rehandshake feature.
@item up- and down- optional scripts.
@end itemize

@node Release 1.1
@section Release 1.1
@itemize
@item FreeBSD support.
@end itemize