Commit 1afc2ed9 authored by Nick Mathewson's avatar Nick Mathewson 🤹
Browse files

Fix policies.c instance of the "if (r=(a-b)) return r" pattern 

I think this one probably can't underflow, since the input ranges
are small.  But let's not tempt fate.

This patch also replaces the "cmp" functions here with just "eq"
functions, since nothing actually checked for anything besides 0 and
nonzero.

Related to 21278.
parent 4a2afd5b

src/or/policies.c

+29 −29
Original line number Diff line number Diff line
@@ -1198,47 +1198,47 @@ policies_parse_from_options(const or_options_t *options) 
  return ret;

}



/** Compare two provided address policy items, and return -1, 0, or 1

/** Compare two provided address policy items, and renturn -1, 0, or 1

 * if the first is less than, equal to, or greater than the second. */

static int

cmp_single_addr_policy(addr_policy_t *a, addr_policy_t *b)

single_addr_policy_eq(const addr_policy_t *a, const addr_policy_t *b)

{

  int r;

  if ((r=((int)a->policy_type - (int)b->policy_type)))

    return r;

  if ((r=((int)a->is_private - (int)b->is_private)))

    return r;

#define CMP_FIELD(field) do {                   \

    if (a->field != b->field) {                 \

      return 0;                                 \

    }                                           \

  } while (0)

  CMP_FIELD(policy_type);

  CMP_FIELD(is_private);

  /* refcnt and is_canonical are irrelevant to equality,

   * they are hash table implementation details */

  if ((r=tor_addr_compare(&a->addr, &b->addr, CMP_EXACT)))

    return r;

  if ((r=((int)a->maskbits - (int)b->maskbits)))

    return r;

  if ((r=((int)a->prt_min - (int)b->prt_min)))

    return r;

  if ((r=((int)a->prt_max - (int)b->prt_max)))

    return r;

    return 0;

  CMP_FIELD(maskbits);

  CMP_FIELD(prt_min);

  CMP_FIELD(prt_max);

#undef CMP_FIELD

  return 1;

}



/** Like cmp_single_addr_policy() above, but looks at the

 * whole set of policies in each case. */

/** As single_addr_policy_eq, but compare every element of two policies.

 */

int

cmp_addr_policies(smartlist_t *a, smartlist_t *b)

addr_policies_eq(const smartlist_t *a, const smartlist_t *b)

{

  int r, i;

  int i;

  int len_a = a ? smartlist_len(a) : 0;

  int len_b = b ? smartlist_len(b) : 0;



  for (i = 0; i < len_a && i < len_b; ++i) {

    if ((r = cmp_single_addr_policy(smartlist_get(a, i), smartlist_get(b, i))))

      return r;

  }

  if (i == len_a && i == len_b)

  if (len_a != len_b)

    return 0;

  if (i < len_a)

    return -1;

  else



  for (i = 0; i < len_a; ++i) {

    if (! single_addr_policy_eq(smartlist_get(a, i), smartlist_get(b, i)))

      return 0;

  }



  return 1;

}
@@ -1255,7 +1255,7 @@ static HT_HEAD(policy_map, policy_map_ent_t) policy_root = HT_INITIALIZER(); 
static inline int

policy_eq(policy_map_ent_t *a, policy_map_ent_t *b)

{

  return cmp_single_addr_policy(a->policy, b->policy) == 0;

  return single_addr_policy_eq(a->policy, b->policy);

}



/** Return a hashcode for <b>ent</b> */
@@ -1306,7 +1306,7 @@ addr_policy_get_canonical_entry(addr_policy_t *e) 
    HT_INSERT(policy_map, &policy_root, found);

  }



  tor_assert(!cmp_single_addr_policy(found->policy, e));

  tor_assert(single_addr_policy_eq(found->policy, e));

  ++found->policy->refcnt;

  return found->policy;

}

src/or/policies.h

+1 −1
Original line number Diff line number Diff line
@@ -76,7 +76,7 @@ void policy_expand_unspec(smartlist_t **policy); 
int policies_parse_from_options(const or_options_t *options);



addr_policy_t *addr_policy_get_canonical_entry(addr_policy_t *ent);

int cmp_addr_policies(smartlist_t *a, smartlist_t *b);

int addr_policies_eq(const smartlist_t *a, const smartlist_t *b);

MOCK_DECL(addr_policy_result_t, compare_tor_addr_to_addr_policy,

    (const tor_addr_t *addr, uint16_t port, const smartlist_t *policy));

addr_policy_result_t compare_tor_addr_to_node_policy(const tor_addr_t *addr,

src/or/routerlist.c

+1 −1
Original line number Diff line number Diff line
@@ -5445,7 +5445,7 @@ router_differences_are_cosmetic(const routerinfo_t *r1, const routerinfo_t *r2) 
      (r1->contact_info && r2->contact_info &&

       strcasecmp(r1->contact_info, r2->contact_info)) ||

      r1->is_hibernating != r2->is_hibernating ||

      cmp_addr_policies(r1->exit_policy, r2->exit_policy) ||

      ! addr_policies_eq(r1->exit_policy, r2->exit_policy) ||

      (r1->supports_tunnelled_dir_requests !=

       r2->supports_tunnelled_dir_requests))

    return 0;

src/test/test_policy.c

+4 −4
Original line number Diff line number Diff line
@@ -304,10 +304,10 @@ test_policies_general(void *arg) 
  tt_assert(!exit_policy_is_general_exit(policy10));

  tt_assert(!exit_policy_is_general_exit(policy11));



  tt_assert(cmp_addr_policies(policy, policy2));

  tt_assert(cmp_addr_policies(policy, NULL));

  tt_assert(!cmp_addr_policies(policy2, policy2));

  tt_assert(!cmp_addr_policies(NULL, NULL));

  tt_assert(!addr_policies_eq(policy, policy2));

  tt_assert(!addr_policies_eq(policy, NULL));

  tt_assert(addr_policies_eq(policy2, policy2));

  tt_assert(addr_policies_eq(NULL, NULL));



  tt_assert(!policy_is_reject_star(policy2, AF_INET, 1));

  tt_assert(policy_is_reject_star(policy, AF_INET, 1));