[tor-bugs] #33618 [Core Tor/Tor]: Add IPv6 Support to is_local_addr()

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#33618: Add IPv6 Support to is_local_addr()
------------------------------------------+--------------------------------
 Reporter:  kimimaro                      |          Owner:  (none)
     Type:  enhancement                   |         Status:  new
 Priority:  Medium                        |      Milestone:  Tor:
                                          |  0.4.4.x-final
Component:  Core Tor/Tor                  |        Version:
 Severity:  Normal                        |     Resolution:
 Keywords:  outreachy-ipv6 ipv6  prop312  |  Actual Points:
Parent ID:                                |         Points:  1
 Reviewer:                                |        Sponsor:  Sponsor55-can
------------------------------------------+--------------------------------

Comment (by kimimaro):

 Current code changes on commit afbf854ee1ef17622748ec4878e8929df8c9dc0c:

 {{{
 // includes added
 #include "feature/relay/router.h"

 /** Return true iff <b>addr</b> is judged to be on the same network as us,
 or
  * on a private network.
  */
 MOCK_IMPL(int,
 is_local_addr, (const tor_addr_t *addr))
 {
   /* Check for an internal IPv4 or IPv6 address */
   if (tor_addr_is_internal(addr, 0))
     return 1;

   /* Check whether ip is on the same /24 as we are. */
   if (get_options()->EnforceDistinctSubnets == 0)
     return 0;
   if (tor_addr_family(addr) == AF_INET) {
     uint32_t ip = tor_addr_to_ipv4h(addr);

     /* It's possible that this next check will hit before the first time
      * resolve_my_address actually succeeds.  (For clients, it is likely
 that
      * resolve_my_address will never be called at all).  In those cases,
      * last_resolved_addr will be 0, and so checking to see whether ip is
 on
      * the same /24 as last_resolved_addr will be the same as checking
 whether
      * it was on net 0, which is already done by tor_addr_is_internal.
      */
     if ((last_resolved_addr & (uint32_t)0xffffff00ul)
         == (ip & (uint32_t)0xffffff00ul))
       return 1;
   }

   /* Check for the same IPv6 /48 as the directory server */
   if (tor_addr_family(addr) == AF_INET6) {
     if (router_get_my_routerinfo() &&
 tor_addr_is_valid(router_get_my_routerinfo()->ipv6_addr, true)) {
       return tor_addr_compare_masked(addr->addr,
 router_get_my_routerinfo()->ipv6_addr, 48, CMP_EXACT);
     }

   }
   return 0;
 }
 }}}

 Here is the error I am getting:


 {{{
 tor ) make test-network
 $CHUTNEY_PATH was not set.
 Assuming test-network.sh will find ./../chutney
   CC       src/app/config/src_core_libtor_app_testing_a-config.o
 src/app/config/config.c: In function ‘is_local_addr__real’:
 src/app/config/config.c:3024:83: error: dereferencing pointer to
 incomplete type ‘routerinfo_t {aka const struct routerinfo_t}’
  _addr_is_valid(router_get_my_routerinfo()->ipv6_addr, true)) {
                                           ^~
 src/app/config/config.c:3025:38: error: incompatible type for argument 1
 of ‘tor_addr_compare_masked’
        return tor_addr_compare_masked(addr->addr,
 router_get_my_routerinfo()->ipv6_addr, 48, CMP_EXACT);
                                       ^~~~
 In file included from ./src/core/or/or.h:53:0,
                  from src/app/config/config.c:65:
 ./src/lib/net/address.h:249:5: note: expected ‘const tor_addr_t * {aka
 const struct tor_addr_t *}’ but argument is of type ‘const union
 <anonymous>’
  int tor_addr_compare_masked(const tor_addr_t *addr1, const tor_addr_t
 *addr2,
      ^~~~~~~~~~~~~~~~~~~~~~~
 Makefile:13398: recipe for target 'src/app/config
 /src_core_libtor_app_testing_a-config.o' failed
 make[1]: *** [src/app/config/src_core_libtor_app_testing_a-config.o] Error
 1
 Makefile:21570: recipe for target 'test-network' failed
 make: *** [test-network] Error 2
 }}}

 Looks like the only declaration I have found for router_get_my_routerinfo
 was this code in router.h:
 {{{
 MOCK_DECL(const routerinfo_t *, router_get_my_routerinfo, (void));
 MOCK_DECL(const routerinfo_t *, router_get_my_routerinfo_with_err,(int
 *err));
 }}}

 I'm not sure what to do next.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/33618#comment:5>
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