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Diffstat (limited to 'src/or/hs_ident.h')
| -rw-r--r-- | src/or/hs_ident.h | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/src/or/hs_ident.h b/src/or/hs_ident.h new file mode 100644 index 0000000000..8f9da30c35 --- /dev/null +++ b/src/or/hs_ident.h @@ -0,0 +1,146 @@ +/* Copyright (c) 2017, The Tor Project, Inc. */ +/* See LICENSE for licensing information */ + +/** + * \file hs_ident.h + * \brief Header file containing circuit and connection identifier data for + * the whole HS subsytem. + * + * \details + * This interface is used to uniquely identify a hidden service on a circuit + * or connection using the service identity public key. Once the circuit or + * connection subsystem calls in the hidden service one, we use those + * identifiers to lookup the corresponding objects like service, intro point + * and descriptor. + * + * Furthermore, the circuit identifier holds cryptographic material needed for + * the e2e encryption on the rendezvous circuit which is set once the + * rendezvous circuit has opened and ready to be used. + **/ + +#ifndef TOR_HS_IDENT_H +#define TOR_HS_IDENT_H + +#include "crypto_ed25519.h" + +#include "hs_common.h" + +/* Length of the rendezvous cookie that is used to connect circuits at the + * rendezvous point. */ +#define HS_REND_COOKIE_LEN DIGEST_LEN + +/* Type of circuit an hs_ident_t object is associated with. */ +typedef enum { + HS_IDENT_CIRCUIT_INTRO = 1, + HS_IDENT_CIRCUIT_RENDEZVOUS = 2, +} hs_ident_circuit_type_t; + +/* Client and service side circuit identifier that is used for hidden service + * circuit establishment. Not all fields contain data, it depends on the + * circuit purpose. This is attached to an origin_circuit_t. All fields are + * used by both client and service. */ +typedef struct hs_ident_circuit_t { + /* (All circuit) The public key used to uniquely identify the service. It is + * the one found in the onion address. */ + ed25519_public_key_t identity_pk; + + /* (All circuit) The type of circuit this identifier is attached to. + * Accessors of the fields in this object assert non fatal on this circuit + * type. In other words, if a rendezvous field is being accessed, the + * circuit type MUST BE of type HS_IDENT_CIRCUIT_RENDEZVOUS. This value is + * set when an object is initialized in its constructor. */ + hs_ident_circuit_type_t circuit_type; + + /* (All circuit) Introduction point authentication key. It's also needed on + * the rendezvous circuit for the ntor handshake. It's used as the unique key + * of the introduction point so it should not be shared between multiple + * intro points. */ + ed25519_public_key_t intro_auth_pk; + + /* (Only client rendezvous circuit) Introduction point encryption public + * key. We keep it in the rendezvous identifier for the ntor handshake. */ + curve25519_public_key_t intro_enc_pk; + + /* (Only rendezvous circuit) Rendezvous cookie sent from the client to the + * service with an INTRODUCE1 cell and used by the service in an + * RENDEZVOUS1 cell. */ + uint8_t rendezvous_cookie[HS_REND_COOKIE_LEN]; + + /* (Only service rendezvous circuit) The HANDSHAKE_INFO needed in the + * RENDEZVOUS1 cell of the service. The construction is as follows: + * SERVER_PK [32 bytes] + * AUTH_MAC [32 bytes] + */ + uint8_t rendezvous_handshake_info[CURVE25519_PUBKEY_LEN + DIGEST256_LEN]; + + /* (Only client rendezvous circuit) Client ephemeral keypair needed for the + * e2e encryption with the service. */ + curve25519_keypair_t rendezvous_client_kp; + + /* (Only rendezvous circuit) The NTOR_KEY_SEED needed for key derivation for + * the e2e encryption with the client on the circuit. */ + uint8_t rendezvous_ntor_key_seed[DIGEST256_LEN]; + + /* (Only rendezvous circuit) Number of streams associated with this + * rendezvous circuit. We track this because there is a check on a maximum + * value. */ + uint64_t num_rdv_streams; +} hs_ident_circuit_t; + +/* Client and service side directory connection identifier used for a + * directory connection to identify which service is being queried. This is + * attached to a dir_connection_t. */ +typedef struct hs_ident_dir_conn_t { + /* The public key used to uniquely identify the service. It is the one found + * in the onion address. */ + ed25519_public_key_t identity_pk; + + /* The blinded public key used to uniquely identify the descriptor that this + * directory connection identifier is for. Only used by the service-side code + * to fine control descriptor uploads. */ + ed25519_public_key_t blinded_pk; + + /* XXX: Client authorization. */ +} hs_ident_dir_conn_t; + +/* Client and service side edge connection identifier used for an edge + * connection to identify which service is being queried. This is attached to + * a edge_connection_t. */ +typedef struct hs_ident_edge_conn_t { + /* The public key used to uniquely identify the service. It is the one found + * in the onion address. */ + ed25519_public_key_t identity_pk; + + /* XXX: Client authorization. */ +} hs_ident_edge_conn_t; + +/* Circuit identifier API. */ +hs_ident_circuit_t *hs_ident_circuit_new( + const ed25519_public_key_t *identity_pk, + hs_ident_circuit_type_t circuit_type); +void hs_ident_circuit_free_(hs_ident_circuit_t *ident); +#define hs_ident_circuit_free(id) \ + FREE_AND_NULL(hs_ident_circuit_t, hs_ident_circuit_free_, (id)) +hs_ident_circuit_t *hs_ident_circuit_dup(const hs_ident_circuit_t *src); + +/* Directory connection identifier API. */ +hs_ident_dir_conn_t *hs_ident_dir_conn_dup(const hs_ident_dir_conn_t *src); +void hs_ident_dir_conn_free_(hs_ident_dir_conn_t *ident); +#define hs_ident_dir_conn_free(id) \ + FREE_AND_NULL(hs_ident_dir_conn_t, hs_ident_dir_conn_free_, (id)) +void hs_ident_dir_conn_init(const ed25519_public_key_t *identity_pk, + const ed25519_public_key_t *blinded_pk, + hs_ident_dir_conn_t *ident); + +/* Edge connection identifier API. */ +hs_ident_edge_conn_t *hs_ident_edge_conn_new( + const ed25519_public_key_t *identity_pk); +void hs_ident_edge_conn_free_(hs_ident_edge_conn_t *ident); +#define hs_ident_edge_conn_free(id) \ + FREE_AND_NULL(hs_ident_edge_conn_t, hs_ident_edge_conn_free_, (id)) + +/* Validators */ +int hs_ident_intro_circ_is_valid(const hs_ident_circuit_t *ident); + +#endif /* !defined(TOR_HS_IDENT_H) */ + |