onion.h (3736B)
1 /* Copyright (c) 2001 Matej Pfajfar. 2 * Copyright (c) 2001-2004, Roger Dingledine. 3 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. 4 * Copyright (c) 2007-2021, The Tor Project, Inc. */ 5 /* See LICENSE for licensing information */ 6 7 /** 8 * \file onion.h 9 * \brief Header file for onion.c. 10 **/ 11 12 #ifndef TOR_ONION_H 13 #define TOR_ONION_H 14 15 struct create_cell_t; 16 struct curve25519_keypair_t; 17 struct curve25519_public_key_t; 18 #include "lib/crypt_ops/crypto_ed25519.h" 19 20 #define MAX_ONIONSKIN_CHALLENGE_LEN 255 21 #define MAX_ONIONSKIN_REPLY_LEN 255 22 23 #define MAX_CREATE_LEN (CELL_PAYLOAD_SIZE - 4) 24 #define MAX_CREATED_LEN (CELL_PAYLOAD_SIZE - 2) 25 26 /** A parsed CREATE, CREATE_FAST, or CREATE2 cell. */ 27 typedef struct create_cell_t { 28 /** The cell command. One of CREATE{,_FAST,2} */ 29 uint8_t cell_type; 30 /** One of the ONION_HANDSHAKE_TYPE_* values */ 31 uint16_t handshake_type; 32 /** The number of bytes used in <b>onionskin</b>. */ 33 uint16_t handshake_len; 34 /** The client-side message for the circuit creation handshake. */ 35 uint8_t onionskin[MAX_CREATE_LEN]; 36 } create_cell_t; 37 38 /** A parsed CREATED, CREATED_FAST, or CREATED2 cell. */ 39 typedef struct created_cell_t { 40 /** The cell command. One of CREATED{,_FAST,2} */ 41 uint8_t cell_type; 42 /** The number of bytes used in <b>reply</b>. */ 43 uint16_t handshake_len; 44 /** The server-side message for the circuit creation handshake. */ 45 uint8_t reply[MAX_CREATED_LEN]; 46 } created_cell_t; 47 48 /** A parsed RELAY_EXTEND or RELAY_EXTEND2 cell */ 49 typedef struct extend_cell_t { 50 /** One of RELAY_EXTEND or RELAY_EXTEND2 */ 51 uint8_t cell_type; 52 /** An IPv4 address and port for the node we're connecting to. */ 53 tor_addr_port_t orport_ipv4; 54 /** An IPv6 address and port for the node we're connecting to. */ 55 tor_addr_port_t orport_ipv6; 56 /** Identity fingerprint of the node we're connecting to.*/ 57 uint8_t node_id[DIGEST_LEN]; 58 /** Ed25519 public identity key. Zero if not set. */ 59 struct ed25519_public_key_t ed_pubkey; 60 /** The "create cell" embedded in this extend cell. Note that unlike the 61 * create cells we generate ourselves, this create cell can have a handshake 62 * type we don't recognize. */ 63 create_cell_t create_cell; 64 } extend_cell_t; 65 66 /** A parsed RELAY_EXTEND or RELAY_EXTEND2 cell */ 67 typedef struct extended_cell_t { 68 /** One of RELAY_EXTENDED or RELAY_EXTENDED2. */ 69 uint8_t cell_type; 70 /** The "created cell" embedded in this extended cell. */ 71 created_cell_t created_cell; 72 } extended_cell_t; 73 74 void create_cell_init(create_cell_t *cell_out, uint8_t cell_type, 75 uint16_t handshake_type, uint16_t handshake_len, 76 const uint8_t *onionskin); 77 int create_cell_parse(create_cell_t *cell_out, const cell_t *cell_in); 78 int created_cell_parse(created_cell_t *cell_out, const cell_t *cell_in); 79 MOCK_DECL(int,extend_cell_parse,(extend_cell_t *cell_out, 80 const uint8_t command, 81 const uint8_t *payload_in, 82 size_t payload_len)); 83 int extended_cell_parse(extended_cell_t *cell_out, const uint8_t command, 84 const uint8_t *payload_in, size_t payload_len); 85 86 int create_cell_format(cell_t *cell_out, const create_cell_t *cell_in); 87 int create_cell_format_relayed(cell_t *cell_out, const create_cell_t *cell_in); 88 int created_cell_format(cell_t *cell_out, const created_cell_t *cell_in); 89 int extend_cell_format(uint8_t *command_out, uint16_t *len_out, 90 uint8_t *payload_out, const extend_cell_t *cell_in); 91 int extended_cell_format(uint8_t *command_out, uint16_t *len_out, 92 uint8_t *payload_out, const extended_cell_t *cell_in); 93 94 #endif /* !defined(TOR_ONION_H) */