Commit bd6ab90a authored by teor's avatar teor
Browse files

core/or: Support IPv6 EXTEND2 cells 

Allow clients and relays to send dual-stack and IPv6-only EXTEND2 cells.
Parse dual-stack and IPv6-only EXTEND2 cells on relays.

Relays do not make connections or extend circuits via IPv6: that's the
next step.

Closes ticket 33901.
parent 3253c357

changes/ticket33901

0 → 100644
+4 −0
Original line number Diff line number Diff line 
  o Minor features (IPv6, relay):

    - Allow clients and relays to send dual-stack and IPv6-only EXTEND2 cells.

      Parse dual-stack and IPv6-only EXTEND2 cells on relays.

      Closes ticket 33901.

src/core/or/onion.c

+34 −7
Original line number Diff line number Diff line
@@ -240,11 +240,21 @@ created_cell_parse(created_cell_t *cell_out, const cell_t *cell_in) 
static int

check_extend_cell(const extend_cell_t *cell)

{

  const bool is_extend2 = (cell->cell_type == RELAY_COMMAND_EXTEND2);



  if (tor_digest_is_zero((const char*)cell->node_id))

    return -1;

  /* We don't currently allow EXTEND2 cells without an IPv4 address */

  if (tor_addr_family(&cell->orport_ipv4.addr) == AF_UNSPEC)

  if (tor_addr_family(&cell->orport_ipv4.addr) == AF_UNSPEC) {

    /* EXTEND cells must have an IPv4 address. */

    if (!is_extend2) {

      return -1;

    }

    /* EXTEND2 cells must have at least one IP address.

     * It can be IPv4 or IPv6. */

    if (tor_addr_family(&cell->orport_ipv6.addr) == AF_UNSPEC) {

      return -1;

    }

  }

  if (cell->create_cell.cell_type == CELL_CREATE) {

    if (cell->cell_type != RELAY_COMMAND_EXTEND)

      return -1;
@@ -364,7 +374,12 @@ extend_cell_from_extend2_cell_body(extend_cell_t *cell_out, 
    }

  }



  if (!found_rsa_id || !found_ipv4) /* These are mandatory */

  /* EXTEND2 cells must have an RSA ID */

  if (!found_rsa_id)

    return -1;



  /* EXTEND2 cells must have at least one IP address */

  if (!found_ipv4 && !found_ipv6)

    return -1;



  return create_cell_from_create2_cell_body(&cell_out->create_cell,
@@ -620,12 +635,13 @@ extend_cell_format(uint8_t *command_out, uint16_t *len_out, 
    break;

  case RELAY_COMMAND_EXTEND2:

    {

      uint8_t n_specifiers = 2;

      uint8_t n_specifiers = 1;

      *command_out = RELAY_COMMAND_EXTEND2;

      extend2_cell_body_t *cell = extend2_cell_body_new();

      link_specifier_t *ls;

      {

        /* IPv4 specifier first. */

      if (tor_addr_port_is_valid_ap(&cell_in->orport_ipv4, 0)) {

        /* Maybe IPv4 specifier first. */

        ++n_specifiers;

        ls = link_specifier_new();

        extend2_cell_body_add_ls(cell, ls);

        ls->ls_type = LS_IPV4;
@@ -651,6 +667,17 @@ extend_cell_format(uint8_t *command_out, uint16_t *len_out, 
        ls->ls_len = 32;

        memcpy(ls->un_ed25519_id, cell_in->ed_pubkey.pubkey, 32);

      }

      if (tor_addr_port_is_valid_ap(&cell_in->orport_ipv6, 0)) {

        /* Then maybe IPv6 specifier. */

        ++n_specifiers;

        ls = link_specifier_new();

        extend2_cell_body_add_ls(cell, ls);

        ls->ls_type = LS_IPV6;

        ls->ls_len = 18;

        tor_addr_get_ipv6_bytes((char *)ls->un_ipv6_addr,

                                &cell_in->orport_ipv6.addr);

        ls->un_ipv6_port = cell_in->orport_ipv6.port;

      }

      cell->n_spec = n_specifiers;



      /* Now, the handshake */

src/lib/net/address.c

+14 −0
Original line number Diff line number Diff line
@@ -903,6 +903,20 @@ tor_addr_from_in6(tor_addr_t *dest, const struct in6_addr *in6) 
  tor_addr_from_ipv6_bytes(dest, (const char*)in6->s6_addr);

}



/** Set the 16 bytes at <b>dest</b> to equal the IPv6 address <b>src</b>.

 * <b>src</b> must be an IPv6 address, if it is not, log a warning, and clear

 * <b>dest</b>. */

void

tor_addr_get_ipv6_bytes(char *dest, const tor_addr_t *src)

{

  tor_assert(dest);

  tor_assert(src);

  memset(dest, 0, 16);

  IF_BUG_ONCE(src->family != AF_INET6)

    return;

  memcpy(dest, src->addr.in6_addr.s6_addr, 16);

}



/** Copy a tor_addr_t from <b>src</b> to <b>dest</b>.

 */

void

src/lib/net/address.h

+1 −0
Original line number Diff line number Diff line
@@ -303,6 +303,7 @@ void tor_addr_from_ipv6_bytes(tor_addr_t *dest, const char *bytes); 
#define tor_addr_from_in(dest, in) \

  tor_addr_from_ipv4n((dest), (in)->s_addr);

void tor_addr_from_in6(tor_addr_t *dest, const struct in6_addr *in6);

void tor_addr_get_ipv6_bytes(char *dest, const tor_addr_t *src);



int tor_addr_is_null(const tor_addr_t *addr);

int tor_addr_is_loopback(const tor_addr_t *addr);

src/test/test_cell_formats.c

+26 −13
Original line number Diff line number Diff line
@@ -713,16 +713,20 @@ test_cfmt_extend_cells(void *arg) 
  tt_mem_op(cc->onionskin,OP_EQ, b, 99+20);

  tt_int_op(0, OP_EQ, extend_cell_format(&p2_cmd, &p2_len, p2, &ec));

  tt_int_op(p2_cmd, OP_EQ, RELAY_COMMAND_EXTEND2);

  /* We'll generate it minus the IPv6 address and minus the konami code */

  tt_int_op(p2_len, OP_EQ, 89+99-34-20);

  /* We'll generate it minus the konami code */

  tt_int_op(p2_len, OP_EQ, 89+99-34);

  test_memeq_hex(p2,

                 /* Two items: one that same darn IP address. */

                 "02000612F40001F0F1"

                 /* The next is a digest : anthropomorphization */

                 "0214616e7468726f706f6d6f727068697a6174696f6e"

                 /* Three items */

                 "03"

                 /* IPv4 address */

                 "0006" "12F40001" "F0F1"

                 /* The next is an RSA digest: anthropomorphization */

                 "0214" "616e7468726f706f6d6f727068697a6174696f6e"

                 /*IPv6 address */

                 "0112" "20020000000000000000000000f0c51e" "1112"

                 /* Now the handshake prologue */

                 "01050063");

  tt_mem_op(p2+1+8+22+4,OP_EQ, b, 99+20);

  tt_mem_op(p2+1+8+22+20+4, OP_EQ, b, 99+20);

  tt_int_op(0, OP_EQ, create_cell_format_relayed(&cell, cc));



  /* Now let's add an ed25519 key to that extend2 cell. */
@@ -732,22 +736,31 @@ test_cfmt_extend_cells(void *arg) 
  /* As before, since we aren't extending by ed25519. */

  get_options_mutable()->ExtendByEd25519ID = 0;

  tt_int_op(0, OP_EQ, extend_cell_format(&p2_cmd, &p2_len, p2, &ec));

  tt_int_op(p2_len, OP_EQ, 89+99-34-20);

  tt_int_op(p2_len, OP_EQ, 89+99-34);

  test_memeq_hex(p2,

                 "02000612F40001F0F1"

                 "03"

                 "000612F40001F0F1"

                 "0214616e7468726f706f6d6f727068697a6174696f6e"

                 "011220020000000000000000000000f0c51e1112"

                 "01050063");



  /* Now try with the ed25519 ID. */

  get_options_mutable()->ExtendByEd25519ID = 1;

  tt_int_op(0, OP_EQ, extend_cell_format(&p2_cmd, &p2_len, p2, &ec));

  tt_int_op(p2_len, OP_EQ, 89+99-34-20 + 34);

  tt_int_op(p2_len, OP_EQ, 89+99);

  test_memeq_hex(p2,

                 "03000612F40001F0F1"

                 /* Four items */

                 "04"

                 /* IPv4 address */

                 "0006" "12F40001" "F0F1"

                 /* The next is an RSA digest: anthropomorphization */

                 "0214616e7468726f706f6d6f727068697a6174696f6e"

                 // ed digest follows:

                 /* Then an ed public key: brownshoesdontmakeit/brownshoesd */

                 "0320" "62726f776e73686f6573646f6e746d616b656"

                        "9742f62726f776e73686f657364"

                 /*IPv6 address */

                 "0112" "20020000000000000000000000f0c51e" "1112"

                 /* Now the handshake prologue */

                 "01050063");

  /* Can we parse that? Did the key come through right? */

  memset(&ec, 0, sizeof(ec));
@@ -816,7 +829,7 @@ test_cfmt_extend_cells(void *arg) 
  memcpy(p+1, "\x02\x14" "anarchoindividualist", 22);

  memcpy(p+23, "\x01\x12" "xxxxxxxxxxxxxxxxYY", 18);

  memcpy(p+41, "\xff\xff\x00\x20", 4);

  tt_int_op(-1, OP_EQ, extend_cell_parse(&ec, RELAY_COMMAND_EXTEND2,

  tt_int_op(0, OP_EQ, extend_cell_parse(&ec, RELAY_COMMAND_EXTEND2,

                                      p, sizeof(p)));



  /* Running out of space in specifiers  */