Pure rust asymmetric crypto

[kurnevsky]

libsodium no more

[coveralls]

Pull Request Test Coverage Report for Build 1154040616

• 3498 of 3780 (92.54%) changed or added relevant lines in 70 files are covered.
• 1024 unchanged lines in 25 files lost coverage.
• Overall coverage decreased (-7.6%) to 86.886%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
tox_core/src/relay/links.rs	54	56	96.43%
tox_crypto/src/lib.rs	21	23	91.3%
tox_core/src/state_format/old.rs	10	13	76.92%
tox_core/src/relay/server/server.rs	41	46	89.13%
tox_core/src/relay/server/server_ext.rs	15	20	75.0%
tox_core/src/onion/client/paths_pool.rs	61	67	91.04%
tox_core/src/relay/client/client.rs	79	102	77.45%
tox_core/src/onion/client/mod.rs	517	543	95.21%
tox_core/src/relay/client/connections.rs	133	181	73.48%
tox_core/src/net_crypto/mod.rs	838	890	94.16%

Files with Coverage Reduction	New Missed Lines	%
tox_binary_io/src/lib.rs	1	91.67%
tox_core/src/dht/dht_node.rs	1	80.0%
tox_core/src/onion/client/nodes_pool.rs	1	87.8%
tox_core/src/relay/links.rs	1	97.75%
tox_core/src/state_format/old.rs	1	82.21%
tox_core/src/udp.rs	1	3.8%
tox_packet/src/messenger/msi.rs	1	79.1%
tox_core/src/io_tokio.rs	2	75.0%
tox_core/src/relay/server/client.rs	2	82.19%
tox_packet/src/dht/macros.rs	2	95.45%

Totals
Change from base Build 1077257580:	-7.6%
Covered Lines:	14430
Relevant Lines:	16608

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💛 - Coveralls

[kpp]

It is fixed

[kurnevsky]

Fixed, but I'd leave it for another MR, because firstly we need to check how many nodes from tox network migrated to a new version.

[kpp]

Do we really have to have NONCEBYTES but not PUBLICKEYBYTES? Why not create an alias to crypto_box::KEY_SIZE?

[kpp]

To be honest I thought we had tox_crypto crate to be able to keep all these consts in one place.

[kurnevsky]

To be honest I thought we had tox_crypto crate to be able to keep all these consts in one place.

It didn't work this way because in tox we have both symmetric and asymmetric crypto, and different kind of hashes. So there are a lot of consts that have same or similar name, but we had here only consts for asymmetric crypto. I'd actually prefer not to redefine consts and import them directly from tox-crypto lib because this way we won't have a confusion - before we used both sodiumoxide and our redefined consts at the same time in different places. As for NONCEBYTES ryst-crypto just don't have a convenient const to use. But I can remove it as well - just using NonceSize::USIZE is good enough for me :)

[kpp]

Why not keep it?

[kurnevsky]

encode_decode_test compares result with Eq, but it's not implemented for secret and precomputed keys.

[kpp]

LGTM