This fixes an error reported by cppcheck about overflowing the callback
array. The locking logic probably was broken, so I replaced it with
something simpler and more robust.
If the `recvbuf` network function returns 0 all the time, that means
there is never any data available on the TCP socket. This change makes
it so there is a random amount of data available on the TCP socket.
This invalidates the bootstrap fuzzer corpus.
This makes more sense as a module for them to live in. Now, util no
longer depends on crypto_core and can thus potentially be used in
crypto_core in the future (functions like min/max may be useful).
It can't happen in almost every reality, except when the RNG is fairly
broken and doesn't add 2 fake DHT friends on startup. Still, this code
should be defensive and never index outside `num_friends` elements.
Right now it only gets built from the first 2 friends in the DHT friend
list: either friend 0 and then 1 or friend 1 and then 0. The randomness
in this code doesn't make sense unless the intention was to select from
all friends, which the code will now do.
Also: use uniform random distribution to select the friends rather than
modulus, which is only uniform for powers of 2.
Ideally this would be able to reach some of the events, so we can write
code to respond to those events, but so far only the friend request
event actually happens.
Disabled a whole bunch of rules from the MISRA-C set. Some of them
should be fixed, but most of the ones we violate have good reasons. This
PR documents those reasons.
This isn't in production yet. It's in the new announce store code. The
problem was that a negative plain_len was converted to unsigned, which
made it a very large number.
`system_random()` can fail and return NULL, which should be handled by
toxencryptsave functions.
Also synced function comments between .h and .c file for toxencryptsave.
Every use of this function needs to allocate the same buffer. None of
the callers uses a differently sized buffer, so we might as well put it
in a struct and have the type checker prove the buffer size is correct.
Also rename `ip_ntoa` to `net_ip_ntoa` to avoid clashes with ESP-IDF
system libraries which define this function as well.
This is the "server-side" part of the new friend finding system,
allowing DHT nodes to store small amounts of data and permit searching
for it. A forwarding (proxying) mechanism allows this to be used by TCP
clients, and deals with non-transitivity in the network.
