This gets rid of the rest of the symbolic links. However, as a consequence, the
crypto header files have now moved to src/, and can no longer contain
library-specific declarations. Therefore, cipher_t, digest_t, ecdh_t, ecdsa_t
and rsa_t are now all opaque types, and only pointers to those types can be
used.
Keep track of the number of correct, non-replayed UDP packets that have been
received, regardless of their content. This can be compared to the sequence
number to determine the real packet loss.
Only the very first packet of an SPTPS session should be send with REQ_KEY,
this signals the peer to abort any previous session and start a new one as
well.
The tree functions were never used on the connection_tree, a list is more appropriate.
Also be more paranoid about connections disappearing while traversing the list.
Similar to old style key exchange requests, keep track of whether a key
exchange is already in progress and how long it took. If no key is known yet
or if key exchange takes too long, (re)start a new key exchange.
When two nodes which support SPTPS want to send packets to each other, they now
always use SPTPS. The node initiating the SPTPS session send the first SPTPS
packet via an extended REQ_KEY messages. All other handshake messages are sent
using ANS_KEY messages. This ensures that intermediate nodes using an older
version of tinc can still help with NAT traversal. After the authentication
phase is over, SPTPS packets are sent via UDP, or are encapsulated in extended
REQ_KEY messages instead of PACKET messages.
This allows tincctl to receive log messages from a running tincd,
independent of what is logged to syslog or to file. Tincctl can receive
debug messages with an arbitrary level.
REQ_KEY requests have an extra field indicating key exchange version.
If it is present and > 0, the sender supports ECDH. If the receiver also
does, then it will generate a new keypair and sends the public key in a
ANS_KEY request with "ECDH:" prefixed. The ans_key_h() function will
compute the shared secret, which, at the moment,is used as is to set the
cipher and HMAC keys. However, this must be changed to use a proper KDF.
In the future, the ECDH key exchange must also be signed.
Before, if MTU probes failed, tinc would stop sending probes until the next
time keys were regenerated (by default, once every hour). Now it continues to
send them every PingInterval, so it recovers faster from temporary failures.
