extern struct zebra_privs_t zserv_privs;
extern struct zebra_t zebrad;
-/* Socket length roundup function. */
+/*
+ * Given a sockaddr length, round it up to include pad bytes following
+ * it. Assumes the kernel pads to sizeof(long).
+ *
+ * XXX: why is ROUNDUP(0) sizeof(long)? 0 is an illegal sockaddr
+ * length anyway (< sizeof (struct sockaddr)), so this shouldn't
+ * matter.
+ */
#define ROUNDUP(a) \
((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
-/* And this macro is wrapper for handling sa_len. */
+/*
+ * Given a pointer (sockaddr or void *), return the number of bytes
+ * taken up by the sockaddr and any padding needed for alignment.
+ */
#if defined(HAVE_SA_LEN)
-#define WRAPUP(X) ROUNDUP(((struct sockaddr *)(X))->sa_len)
+#define SAROUNDUP(X) ROUNDUP(((struct sockaddr *)(X))->sa_len)
#elif defined(HAVE_IPV6)
-#define WRAPUP(X) \
+/*
+ * One would hope all fixed-size structure definitions are aligned,
+ * but round them up nonetheless.
+ */
+#define SAROUNDUP(X) \
do { \
(((struct sockaddr *)(X))->sa_family == AF_INET ? \
ROUNDUP(sizeof(struct sockaddr_in)):\
ROUNDUP(sizeof(struct sockaddr_dl)) : sizeof(struct sockaddr)))) \
} while (0)
#else /* HAVE_IPV6 */
-#define WRAPUP(X) \
+#define SAROUNDUP(X) \
(((struct sockaddr *)(X))->sa_family == AF_INET ? \
ROUNDUP(sizeof(struct sockaddr_in)):\
(((struct sockaddr *)(X))->sa_family == AF_LINK ? \
{
struct interface *ifp = NULL;
struct sockaddr_dl *sdl = NULL;
+ void *cp;
+ unsigned int i;
char ifname[IFNAMSIZ];
/* paranoia: sanity check structure */
}
/*
- * Check for a sockaddr_dl following the message.
+ * Check for a sockaddr_dl following the message. First, point to
+ * where a socakddr might be if one follows the message.
*/
-#ifdef SUNOS_5
- int i;
- struct sockaddr *sa;
- u_char *cp = (u_char *)(ifm + 1);
+ cp = (void *)(ifm + 1);
+#ifdef SUNOS_5
/*
+ * XXX This behavior should be narrowed to only the kernel versions
+ * for which the structures returned do not match the headers.
+ *
* if_msghdr_t on 64 bit kernels in Solaris 9 and earlier versions
- * is 12 bytes larger than the 32 bit version, so make adjustment
- * here.
+ * is 12 bytes larger than the 32 bit version.
*/
- sa = (struct sockaddr *)cp;
- if (sa->sa_family == AF_UNSPEC)
+ if (((struct sockaddr *) cp)->sa_family == AF_UNSPEC)
cp = cp + 12;
+#endif
+ /*
+ * Check for each sockaddr in turn, advancing over it. After this
+ * loop, sdl should point to a sockaddr_dl iff one was present.
+ */
for (i = 1; i != 0; i <<= 1)
{
- if (i & ifm->ifm_addrs)
+ if (i & ifm->ifm_addrs)
{
- sa = (struct sockaddr *)cp;
- cp += WRAPUP(sa);
- if (i & RTA_IFP)
+ if (i == RTA_IFP)
{
- sdl = (struct sockaddr_dl *)sa;
+ sdl = (struct sockaddr_dl *)cp;
break;
}
+ cp += SAROUNDUP(cp);
}
}
- /*
- * After here, If RTA_IFP was set in ifm_addrs, sdl should point to
- * the sockaddr_dl.
- */
-#else
- /* sockaddrs_present? */
- if (ifm->ifm_addrs)
+
+ /* Ensure that sdl, if present, is actually a sockaddr_dl. */
+ if (sdl != NULL && sdl->sdl_family != AF_LINK)
{
- if (ifm->ifm_addrs == RTA_IFP)
- {
- /* just the one we want */
- sdl = (struct sockaddr_dl *)(ifm + 1);
- }
- else
- {
- /*
- * Not strictly an error, but more complicated parsing than
- * is implemented is required to handle this case.
- */
- zlog_err ("ifm_read: addrs %x != RTA_IFP (unhandled, ignoring)\n",
- ifm->ifm_addrs);
- return -1;
- }
+ zlog_err ("ifm_read: sockaddr_dl bad AF %d\n",
+ sdl->sdl_family);
+ return -1;
}
- /*
- * Past here, either ifm_addrs == 0 or ifm_addrs == RTA_IFP and sdl
- * points to a RTA_IFP sockaddr.
- */
-#endif
-
- /* Check that sdl, if present, is actually a sockaddr_dl before use. */
- if (sdl != NULL)
- switch (sdl->sdl_family)
- {
- case AF_LINK:
- /* Standard AF for link-layer address sockaddrs. */
- case AF_DLI:
- /*
- * XXX Comment in NetBSD net/if_dl.h says AF_DLI, but this
- * seems wrong. Accept it for now.
- */
- break;
-
- default:
- zlog_err ("ifm_read: sockaddr_dl bad AF %d\n",
- sdl->sdl_family);
- return -1;
- }
/*
- * Look up on ifindex. This is useful if this is an up/down
- * notification for an interface of which we are already aware.
- * (This happens on NetBSD 1.6.2, for example.)
+ * Look up on ifindex first, because ifindices are the primary
+ * handle for interfaces across the user/kernel boundary. (Some
+ * messages, such as up/down status changes on NetBSD, do not
+ * include a sockaddr_dl).
*/
- if (ifp == NULL)
- ifp = if_lookup_by_index (ifm->ifm_index);
+ ifp = if_lookup_by_index (ifm->ifm_index);
/*
* If lookup by index was unsuccessful and we have a name, try
*/
if ((ifp == NULL) || (ifp->ifindex == -1))
{
- /* Check interface's address.*/
- if (! (ifm->ifm_addrs & RTA_IFP))
- {
- zlog_warn ("Interface index %d (new) missing RTA_IFP sockaddr\n",
- ifm->ifm_index);
- return -1;
- }
-
/*
- * paranoia: sdl-finding code above guarantees that sdl is
- * non-NULL and valid if RTA_IFP is set in ifm_addrs, so this
- * check is in theory not necessary.
+ * To create or fill in an interface, a sockaddr_dl (via
+ * RTA_IFP) is required.
*/
if (sdl == NULL)
{
- zlog_warn ("ifm_read: no sockaddr_dl present");
+ zlog_warn ("Interface index %d (new) missing RTA_IFP sockaddr_dl\n",
+ ifm->ifm_index);
return -1;
}
if (ifp == NULL)
+ /* Interface that zebra was not previously aware of, so create. */
ifp = if_create (sdl->sdl_data, sdl->sdl_nlen);
+ /*
+ * Fill in newly created interface structure, or larval
+ * structure with ifindex -1.
+ */
ifp->ifindex = ifm->ifm_index;
ifp->flags = ifm->ifm_flags;
#if defined(__bsdi__)
#endif /* __bsdi__ */
if_get_metric (ifp);
- /* Fetch hardware address. */
- if (sdl->sdl_family != AF_LINK)
- {
- zlog_warn ("sockaddr_dl->sdl_family is not AF_LINK");
- return -1;
- }
- /* XXX sockaddr_dl can be larger than base structure */
+ /*
+ * XXX sockaddr_dl contents can be larger than the structure
+ * definition, so the user of the stored structure must be
+ * careful not to read off the end.
+ */
memcpy (&ifp->sdl, sdl, sizeof (struct sockaddr_dl));
if_add_update (ifp);
#define IFAMADDRGET(X,R) \
if (ifm->ifam_addrs & (R)) \
{ \
- int len = WRAPUP(pnt); \
+ int len = SAROUNDUP(pnt); \
if (((X) != NULL) && af_check (((struct sockaddr *)pnt)->sa_family)) \
memcpy ((caddr_t)(X), pnt, len); \
pnt += len; \
#define IFAMMASKGET(X,R) \
if (ifm->ifam_addrs & (R)) \
{ \
- int len = WRAPUP(pnt); \
+ int len = SAROUNDUP(pnt); \
if ((X) != NULL) \
memcpy ((caddr_t)(X), pnt, len); \
pnt += len; \
#define RTMADDRGET(X,R) \
if (rtm->rtm_addrs & (R)) \
{ \
- int len = WRAPUP (pnt); \
+ int len = SAROUNDUP (pnt); \
if (((X) != NULL) && af_check (((struct sockaddr *)pnt)->sa_family)) \
memcpy ((caddr_t)(X), pnt, len); \
pnt += len; \
#define RTMMASKGET(X,R) \
if (rtm->rtm_addrs & (R)) \
{ \
- int len = WRAPUP (pnt); \
+ int len = SAROUNDUP (pnt); \
if ((X) != NULL) \
memcpy ((caddr_t)(X), pnt, len); \
pnt += len; \
projects / matthieu / frr.git / commitdiff