diff options
| author | Uwe Kleine-König <uwe@kleine-koenig.org> | 2019-11-20 19:11:31 +0100 |
|---|---|---|
| committer | Hans Dedecker <dedeckeh@gmail.com> | 2019-11-29 18:39:31 +0100 |
| commit | e45b1408284c05984b38a910a1f0a07d6c761397 (patch) | |
| tree | 0e139fb4950259f0e79e2700812e6747f2b52bd7 | |
| parent | e15147c272201eb17320c10ec95919e641bd03c5 (diff) | |
interface: warn if ip6hint is truncated
When for example a /60 is assigned to a network the last 4 bits of the
ip6hint are unused. Emit a warning if any of these unused bits is set as
it indicates that someone didn't understand how the hint is used. (As I
did earlier today resulting in spending some time understanding the
code.)
Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
| -rw-r--r-- | interface.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/interface.c b/interface.c index 028dc6c..2fa0613 100644 --- a/interface.c +++ b/interface.c @@ -863,9 +863,15 @@ interface_alloc(const char *name, struct blob_attr *config, bool dynamic) } iface->assignment_hint = -1; - if ((cur = tb[IFACE_ATTR_IP6HINT])) - iface->assignment_hint = strtol(blobmsg_get_string(cur), NULL, 16) & - ~((1 << (64 - iface->assignment_length)) - 1); + if ((cur = tb[IFACE_ATTR_IP6HINT])) { + int32_t assignment_hint = strtol(blobmsg_get_string(cur), NULL, 16); + + iface->assignment_hint = assignment_hint & ~((1 << (64 - iface->assignment_length)) - 1); + + if (iface->assignment_hint != assignment_hint) + netifd_log_message(L_WARNING, "Using truncated assignment hint %d (0x%x) for interface '%s'\n", + iface->assignment_hint, iface->assignment_hint, iface->name); + } if ((cur = tb[IFACE_ATTR_IP6CLASS])) interface_add_assignment_classes(iface, cur); |