[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):

 {{{
 // includes
 #include "feature/relay/router.h"
 #include "feature/nodelist/routerinfo_st.h"

 // modified function
 /** 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,
 &(router_get_my_routerinfo()->ipv6_addr), 48, CMP_EXACT);
     }

   }
   return 0;
 }
 }}}

 The error is quite interesting now:
 {{{
 tor ) make test-network
 $CHUTNEY_PATH was not set.
 Assuming test-network.sh will find ./../chutney
 Running IPv4 flavors: bridges+hs-v23.
 ping6 ::1 or ping ::1 succeeded, running IPv6 flavors: single-
 onion-v23-ipv6-md.
 FAIL: bridges+hs-v23
 cat:
 '/home/seneca/Documents/outreachy/tor/../chutney/net/nodes/*/info.log': No
 such file or directory
 FAIL: single-onion-v23-ipv6-md
 cat:
 '/home/seneca/Documents/outreachy/tor/../chutney/net/nodes/*/info.log': No
 such file or directory
 Log and result files are available in ./test_network_log.
 Makefile:21723: recipe for target 'test-network-results' failed
 make[1]: *** [test-network-results] Error 1
 Makefile:21570: recipe for target 'test-network' failed
 make: *** [test-network] Error 2

 tor ) wc -l test_network_log/*
    670 test_network_log/bridges+hs-v23.log
      4 test_network_log/bridges+hs-v23.trs
    599 test_network_log/single-onion-v23-ipv6-md.log
      4 test_network_log/single-onion-v23-ipv6-md.trs
   1277 total
 }}}

 Please tell me if you want me to attach the logs.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/33618#comment:7>
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