From ab4578302d6968fe420db0951c5291c65c631e51 Mon Sep 17 00:00:00 2001 From: Thomas Haller Date: Wed, 10 Jan 2018 16:33:13 +0100 Subject: device: refactor nm_device_set_ip_ifindex() and set_ip_iface() - don't even bother to look into the platform cache, but use if_indextoname() / if_nametoindex(). In most cases, we obtained the ifindex/ifname not from the platform cache in the first place. Hence, there is a race, where the interface might not exist. However, try to process events of the platform cache, hoping that the cache contains an interface for the given ifindex/ifname. - let set_ip_ifindex() and set_ip_iface() both return a boolean value to indicate whether a ip-interface is set or not. That is, whether we have a positive ip_ifindex. That seems more interesting information, then to return whether anything changed. - as before, set_ip_ifindex() can only clear an ifindex/ifname, or error out without doing anything. That is different from set_ip_iface(), which will also set an ifname if no ifindex can be resolved. That is curreently ugly, because then ip-ifindex and ip-iface don't agree. That shall be improved in the future by: - trying to set an interface that cannot be resolved shall lead to a disconnect in any case. - we shall make less use of the ip-iface and rely more on the ifindex. --- src/devices/nm-device.c | 148 ++++++++++++++++--------------------- src/devices/wwan/nm-device-modem.c | 6 +- 2 files changed, 65 insertions(+), 89 deletions(-) diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c index ecdf7c2008..084c3f7ae4 100644 --- a/src/devices/nm-device.c +++ b/src/devices/nm-device.c @@ -1282,126 +1282,102 @@ nm_device_get_ip_ifindex (const NMDevice *self) return priv->ip_iface ? priv->ip_ifindex : priv->ifindex; } -gboolean -nm_device_set_ip_ifindex (NMDevice *self, int ifindex) +static void +_set_ip_ifindex (NMDevice *self, + int ifindex, + const char *ifname) { - NMDevicePrivate *priv; + NMDevicePrivate *priv = NM_DEVICE_GET_PRIVATE (self); NMPlatform *platform; - const char *name = NULL; + gboolean eq_name; - g_return_val_if_fail (NM_IS_DEVICE (self), FALSE); + /* we can set only the ifname without ifindex (to indicate that this + * is an ip-interface, but lookup for the ifindex failed. + * But we cannot just set ifindex > 0 without an ifname. */ + nm_assert (ifindex <= 0 || ifname); - priv = NM_DEVICE_GET_PRIVATE (self); - platform = nm_device_get_platform (self); + /* normalize ifindex */ + if (ifindex < 0) + ifindex = 0; - if (ifindex > 0) { - const NMPlatformLink *plink; + eq_name = nm_streq0 (priv->ip_iface, ifname); - plink = nm_platform_link_get (platform, ifindex); - if (!plink) { - nm_platform_process_events (platform); - plink = nm_platform_link_get (NM_PLATFORM_GET, ifindex); - } - if (!plink) { - _LOGW (LOGD_DEVICE, "ip-ifindex: ifindex %d not found", ifindex); - return FALSE; - } - name = plink->name; - } else - g_return_val_if_fail (ifindex == 0, FALSE); + if ( eq_name + && priv->ip_ifindex == ifindex) + return; - if (priv->ip_ifindex == ifindex) - return TRUE; + _LOGD (LOGD_DEVICE, "ip-ifindex: update ip-interface to %s%s%s, ifindex %d", + NM_PRINT_FMT_QUOTE_STRING (ifname), + ifindex); - _LOGD (LOGD_DEVICE, "ip-ifindex: update ifindex to %d", ifindex); priv->ip_ifindex = ifindex; - if (!nm_streq0 (priv->ip_iface, name)) { - _LOGD (LOGD_DEVICE, "ip-ifindex: update ip-iface to %s%s%s", - NM_PRINT_FMT_QUOTED (name, "\"", name, "\"", "NULL")); - priv->ip_iface = g_strdup (name); + if (!eq_name) { + g_free (priv->ip_iface); + priv->ip_iface = g_strdup (ifname); _notify (self, PROP_IP_IFACE); } if (priv->ip_ifindex > 0) { - if (nm_platform_check_kernel_support (nm_device_get_platform (self), + platform = nm_device_get_platform (self); + + nm_platform_process_events_ensure_link (platform, + priv->ip_ifindex, + priv->ip_iface); + + if (nm_platform_check_kernel_support (platform, NM_PLATFORM_KERNEL_SUPPORT_USER_IPV6LL)) - nm_platform_link_set_user_ipv6ll_enabled (nm_device_get_platform (self), priv->ip_ifindex, TRUE); + nm_platform_link_set_user_ipv6ll_enabled (platform, priv->ip_ifindex, TRUE); - if (!nm_platform_link_is_up (nm_device_get_platform (self), priv->ip_ifindex)) - nm_platform_link_set_up (nm_device_get_platform (self), priv->ip_ifindex, NULL); + if (!nm_platform_link_is_up (platform, priv->ip_ifindex)) + nm_platform_link_set_up (platform, priv->ip_ifindex, NULL); } /* We don't care about any saved values from the old iface */ g_hash_table_remove_all (priv->ip6_saved_properties); +} - return TRUE; +gboolean +nm_device_set_ip_ifindex (NMDevice *self, int ifindex) +{ + char ifname_buf[IFNAMSIZ]; + const char *ifname = NULL; + + g_return_val_if_fail (NM_IS_DEVICE (self), FALSE); + + if (ifindex > 0) { + ifname = nm_platform_if_indextoname (nm_device_get_platform (self), ifindex, ifname_buf); + if (!ifname) { + _LOGW (LOGD_DEVICE, "ip-ifindex: ifindex %d not found", ifindex); + return FALSE; + } + } + + _set_ip_ifindex (self, ifindex, ifname); + return ifindex > 0; } /** * nm_device_set_ip_iface: * @self: the #NMDevice - * @iface: the new IP interface name + * @ifname: the new IP interface name * * Updates the IP interface name and possibly the ifindex. * - * Returns: %TRUE if the anything (name or ifindex) changed, %FALSE if nothing - * changed. + * Returns: %TRUE if an interface with name @ifname exists, + * and %FALSE, if @ifname is %NULL or no such interface exists. */ gboolean -nm_device_set_ip_iface (NMDevice *self, const char *iface) +nm_device_set_ip_iface (NMDevice *self, const char *ifname) { - NMDevicePrivate *priv; - int ifindex; + int ifindex = 0; g_return_val_if_fail (NM_IS_DEVICE (self), FALSE); - priv = NM_DEVICE_GET_PRIVATE (self); - if (nm_streq0 (iface, priv->ip_iface)) { - if (!iface) - return FALSE; - ifindex = nm_platform_if_nametoindex (nm_device_get_platform (self), iface); - if ( ifindex <= 0 - || priv->ip_ifindex == ifindex) - return FALSE; - - priv->ip_ifindex = ifindex; - _LOGD (LOGD_DEVICE, "ip-ifname: update ifindex for ifname '%s': %d", iface, priv->ip_ifindex); - } else { - g_free (priv->ip_iface); - priv->ip_iface = g_strdup (iface); - - if (iface) { - /* The @iface name is not in sync with the platform cache. - * So, there is no point asking the platform cache to resolve - * the ifindex. Instead, we can only hope that the interface - * with this name still exists and we resolve the ifindex - * anew. - */ - priv->ip_ifindex = nm_platform_if_nametoindex (nm_device_get_platform (self), iface); - if (priv->ip_ifindex > 0) - _LOGD (LOGD_DEVICE, "ip-ifname: set ifname '%s', ifindex %d", iface, priv->ip_ifindex); - else - _LOGW (LOGD_DEVICE, "ip-ifname: set ifname '%s', unknown ifindex", iface); - } else { - priv->ip_ifindex = 0; - _LOGD (LOGD_DEVICE, "ip-ifname: clear ifname"); - } - } - - if (priv->ip_ifindex > 0) { - if (nm_platform_check_kernel_support (nm_device_get_platform (self), - NM_PLATFORM_KERNEL_SUPPORT_USER_IPV6LL)) - nm_platform_link_set_user_ipv6ll_enabled (nm_device_get_platform (self), priv->ip_ifindex, TRUE); + if (ifname) + ifindex = nm_platform_if_nametoindex (nm_device_get_platform (self), ifname); - if (!nm_platform_link_is_up (nm_device_get_platform (self), priv->ip_ifindex)) - nm_platform_link_set_up (nm_device_get_platform (self), priv->ip_ifindex, NULL); - } - - /* We don't care about any saved values from the old iface */ - g_hash_table_remove_all (priv->ip6_saved_properties); - - _notify (self, PROP_IP_IFACE); - return TRUE; + _set_ip_ifindex (self, ifindex, ifname); + return ifindex > 0; } static gboolean @@ -12941,7 +12917,7 @@ _cleanup_generic_post (NMDevice *self, CleanupType cleanup_type) * those are identified by ip_iface, not by iface (which might be a tty * or ATM device). */ - nm_device_set_ip_iface (self, NULL); + _set_ip_ifindex (self, 0, NULL); } /* diff --git a/src/devices/wwan/nm-device-modem.c b/src/devices/wwan/nm-device-modem.c index ccf6e17da2..cec9e5327b 100644 --- a/src/devices/wwan/nm-device-modem.c +++ b/src/devices/wwan/nm-device-modem.c @@ -263,17 +263,17 @@ static void data_port_changed_cb (NMModem *modem, GParamSpec *pspec, gpointer user_data) { NMDevice *self = NM_DEVICE (user_data); - gboolean changed; + gboolean has_ifindex; /* We set the IP iface in the device as soon as we know it, so that we * properly ifup it if needed */ - changed = nm_device_set_ip_iface (self, nm_modem_get_data_port (modem)); + has_ifindex = nm_device_set_ip_iface (self, nm_modem_get_data_port (modem)); /* Disable IPv6 immediately on the interface since NM handles IPv6 * internally, and leaving it enabled could allow the kernel's IPv6 * RA handling code to run before NM is ready. */ - if (changed) + if (has_ifindex) nm_device_ipv6_sysctl_set (self, "disable_ipv6", "1"); } -- cgit v1.2.1