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cell_introduce1.trunnel (3007B)

      1 /*
      2  * This contains the definition of the INTRODUCE1 and INTRODUCE_ACK cell for
      3  * onion service version 3 and onward. The following format is specified in
      4  * proposal 224 section 3.2.
      5  */
      6 
      7 /* From cell_common.trunnel. */
      8 extern struct trn_extension;
      9 /* From ed25519_cert.trunnel. */
     10 extern struct link_specifier;
     11 
     12 const TRUNNEL_SHA1_LEN = 20;
     13 const TRUNNEL_REND_COOKIE_LEN = 20;
     14 
     15 /* Introduce ACK status code. */
     16 const TRUNNEL_HS_INTRO_ACK_STATUS_SUCCESS    = 0x0000;
     17 const TRUNNEL_HS_INTRO_ACK_STATUS_UNKNOWN_ID = 0x0001;
     18 const TRUNNEL_HS_INTRO_ACK_STATUS_BAD_FORMAT = 0x0002;
     19 
     20 /* Authentication key type. */
     21 const TRUNNEL_HS_INTRO_AUTH_KEY_TYPE_LEGACY0 = 0x00;
     22 const TRUNNEL_HS_INTRO_AUTH_KEY_TYPE_LEGACY1 = 0x01;
     23 const TRUNNEL_HS_INTRO_AUTH_KEY_TYPE_ED25519 = 0x02;
     24 
     25 /* Onion key type. */
     26 const TRUNNEL_HS_INTRO_ONION_KEY_TYPE_NTOR = 0x01;
     27 
     28 /* INTRODUCE1 payload. See details in section 3.2.1. */
     29 struct trn_cell_introduce1 {
     30   /* Always zeroed. MUST be checked explicitly by the caller. */
     31   u8 legacy_key_id[TRUNNEL_SHA1_LEN];
     32 
     33   /* Authentication key material. */
     34   u8 auth_key_type IN [TRUNNEL_HS_INTRO_AUTH_KEY_TYPE_LEGACY0,
     35                        TRUNNEL_HS_INTRO_AUTH_KEY_TYPE_LEGACY1,
     36                        TRUNNEL_HS_INTRO_AUTH_KEY_TYPE_ED25519];
     37   u16 auth_key_len;
     38   u8 auth_key[auth_key_len];
     39 
     40   /* Extension(s). Reserved fields. */
     41   struct trn_extension extensions;
     42 
     43   /* Variable length, up to the end of cell. */
     44   u8 encrypted[];
     45 };
     46 
     47 /* INTRODUCE_ACK payload. See details in section 3.2.2. */
     48 struct trn_cell_introduce_ack {
     49   /* Status of introduction. */
     50   u16 status;
     51 
     52   /* Extension(s). Reserved fields. */
     53   struct trn_extension extensions;
     54 };
     55 
     56 /* Encrypted section of the INTRODUCE1/INTRODUCE2 cell. */
     57 struct trn_cell_introduce_encrypted {
     58   /* Rendezvous cookie. */
     59   u8 rend_cookie[TRUNNEL_REND_COOKIE_LEN];
     60 
     61   /* Extension(s). Reserved fields. */
     62   struct trn_extension extensions;
     63 
     64   /* Onion key material. */
     65   u8 onion_key_type IN [TRUNNEL_HS_INTRO_ONION_KEY_TYPE_NTOR];
     66   u16 onion_key_len;
     67   u8 onion_key[onion_key_len];
     68 
     69   /* Link specifiers(s) */
     70   u8 nspec;
     71   struct link_specifier nspecs[nspec];
     72 
     73   /* Optional padding. This might be empty or not. */
     74   u8 pad[];
     75 };
     76 
     77 /*
     78  * INTRODUCE1 cell (encrypted section) extensions.
     79  */
     80 
     81 /* Cell extenstion type Congestion Control Request. */
     82 const TRUNNEL_EXT_TYPE_CC_REQUEST = 0x01;
     83 /* Cell extension type PoW. */
     84 const TRUNNEL_EXT_TYPE_POW = 0x02;
     85 
     86 /*
     87  * PoW Solution Extension. Proposal 327.
     88  */
     89 
     90 const TRUNNEL_POW_NONCE_LEN = 16;
     91 const TRUNNEL_POW_SOLUTION_LEN = 16;
     92 const TRUNNEL_POW_SEED_HEAD_LEN = 4;
     93 
     94 /* Version 1 is based on Equi-X scheme. */
     95 const TRUNNEL_POW_VERSION_EQUIX = 0x01;
     96 
     97 struct trn_cell_extension_pow {
     98   /* Type of PoW system used. */
     99   u8 pow_version IN [0x01];
    100 
    101   /* Nonce */
    102   u8 pow_nonce[TRUNNEL_POW_NONCE_LEN];
    103 
    104   /* Effort */
    105   u32 pow_effort;
    106 
    107   /* Identifiable prefix from the seed. */
    108   u8 pow_seed[TRUNNEL_POW_SEED_HEAD_LEN];
    109 
    110   /* Solution. */
    111   u8 pow_solution[TRUNNEL_POW_SOLUTION_LEN];
    112 };