Green Sky
227425b90e
git-subtree-dir: external/toxcore/c-toxcore git-subtree-split: 67badf69416a74e74f6d7eb51dd96f37282b8455
55 lines
2.3 KiB
Markdown
55 lines
2.3 KiB
Markdown
Encryption library used: http://nacl.cr.yp.to/
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When running the program for the first time the crypto_box_keypair() function is used to
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generate the users public-private key pair. (32 bytes each)
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The generated public key is set as the client_id of the peer.
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Adding a friend
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---------------
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Alice adds Bob to her friend list by adding his 32 byte public key (client_id) to her friend list.
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2 cases:
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case 1: Alice adds the public key of Bob, then Bob waits for Alice to attempt to connect to him.
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case 2: Bob and Alice add their respective public keys to their friend lists at the same time.
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case 1:
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Alice sends an onion data (see: Prevent_tracking.txt) packet to Bob with the encrypted part containing the friend request like so:
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```
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[char with a value of 32][nospam number (4 bytes)][Message]
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```
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Ex message: hello Bob it's me Alice -_- add me pl0x.
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For more info on the nospam see: Spam_Prevention.txt
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Bob receives the request and decrypts the message using the function crypto_box_open()
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If the message decrypts successfully:
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If Alice is already in Bob's friend list: case 2
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If Alice is not in Bob's friend list and the nospam is good: Bob is prompt to add Alice and is shown the message from her.
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If Bob accepts Alice friend request he adds her public key to his friend list.
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case 2:
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Bob and Alice both have the others public key in their friend list, they are ready for the next step: Connecting to an already added friend
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In the next step only crypto_box() is used for encryption and only crypto_box_open() for decryption (just like in the last step.)
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Connecting to an already added friend
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-------------------------------------
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see: Tox_middle_level_network_protocol.txt
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Crypto request packets
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--------------------------------------
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```
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[char with a value of 32][Bob (The receiver's) Public key (client_id) (32 bytes))][Alice's (The sender's) Public key (client_id) (32 bytes)][Random nonce (24 bytes)][Encrypted message]
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```
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The encrypted message is encrypted with crypto_box() (using Bob's public key, Alice's private key and the nonce (randomly generated 24 bytes)) and is a message from Alice in which she tells Bob who she is.
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Each node can route the request to the receiver if they are connected to him. This is to bypass bad NATs.
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