4596 Callers of ip_srcid_find_id() need to be more careful

*** 19,28 ****
--- 19,30 ----
   * CDDL HEADER END
   */
  /*
   * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
+  *
+  * Copyright 2014, OmniTI Computer Consulting, Inc. All rights reserved.
   */
  
  /*
   * This is used to support the hidden __sin6_src_id in the sockaddr_in6
   * structure which is there to ensure that applications (such as UDP apps)
*** 221,251 ****
  }
  
  /*
   * Map from a source id to an address.
   * If the id is unknown return the unspecified address.
   */
! void
  ip_srcid_find_id(uint_t id, in6_addr_t *addr, zoneid_t zoneid,
!     netstack_t *ns)
  {
          srcid_map_t     **smpp;
          srcid_map_t     *smp;
          ip_stack_t      *ipst = ns->netstack_ip;
  
          rw_enter(&ipst->ips_srcid_lock, RW_READER);
          smpp = srcid_lookup_id(id, ipst);
          smp = *smpp;
          if (smp == NULL || (smp->sm_zoneid != zoneid && zoneid != ALL_ZONES)) {
                  /* Not preset */
                  ip1dbg(("ip_srcid_find_id: unknown %u or in wrong zone\n", id));
                  *addr = ipv6_all_zeros;
          } else {
                  ASSERT(smp->sm_refcnt != 0);
                  *addr = smp->sm_addr;
          }
          rw_exit(&ipst->ips_srcid_lock);
  }
  
  /* Assign the next available ID */
  static uint_t
  srcid_nextid(ip_stack_t *ipst)
--- 223,274 ----
  }
  
  /*
   * Map from a source id to an address.
   * If the id is unknown return the unspecified address.
+  *
+  * For known IDs, check if the returned address is v4mapped or not, and
+  * return B_TRUE if it matches the desired v4mapped state or not.  This
+  * prevents a broken app from requesting (via __sin6_src_id) a v4mapped
+  * address for a v6 destination, or vice versa.
+  *
+  * "addr" will not be set if we return B_FALSE.
   */
! boolean_t
  ip_srcid_find_id(uint_t id, in6_addr_t *addr, zoneid_t zoneid,
!     boolean_t v4mapped, netstack_t *ns)
  {
          srcid_map_t     **smpp;
          srcid_map_t     *smp;
          ip_stack_t      *ipst = ns->netstack_ip;
+         boolean_t       rc;
  
          rw_enter(&ipst->ips_srcid_lock, RW_READER);
          smpp = srcid_lookup_id(id, ipst);
          smp = *smpp;
          if (smp == NULL || (smp->sm_zoneid != zoneid && zoneid != ALL_ZONES)) {
                  /* Not preset */
                  ip1dbg(("ip_srcid_find_id: unknown %u or in wrong zone\n", id));
                  *addr = ipv6_all_zeros;
+                 rc = B_TRUE;
          } else {
                  ASSERT(smp->sm_refcnt != 0);
+                 /*
+                  * The caller tells us if it expects a v4mapped address.
+                  * Use it, along with the property of "addr" to set the rc.
+                  */
+                 if (IN6_IS_ADDR_V4MAPPED(&smp->sm_addr))
+                         rc = v4mapped;  /* We want a v4mapped address. */
+                 else
+                         rc = !v4mapped; /* We don't want a v4mapped address. */
+ 
+                 if (rc)
                          *addr = smp->sm_addr;
+ 
          }
          rw_exit(&ipst->ips_srcid_lock);
+         return (rc);
  }
  
  /* Assign the next available ID */
  static uint_t
  srcid_nextid(ip_stack_t *ipst)