From 3d26347d0042313be3c9347f8d82c4ccea67fe68 Mon Sep 17 00:00:00 2001 From: Hans Dedecker Date: Tue, 11 Feb 2014 08:30:20 +0000 Subject: [PATCH] netifd: Link layer state awareness support on device level Device layer is informed by netlink events regarding the link layer status. Link layer status change results in a DEV_EVENT_LINK_UP/DEV_EVENT_LINK_DOWN broadcast event for a given device. Depends on uloop error callback patch. Solves issue reported in https://dev.openwrt.org/ticket/14590 Signed-off-by: Hans Dedecker Acked-by: Karl Vogel --- device.c | 29 +++++++++- device.h | 4 ++ system-linux.c | 154 +++++++++++++++++++++++++++++++++++++++++-------- 3 files changed, 162 insertions(+), 25 deletions(-) diff --git a/device.c b/device.c index feeb290..6a770ac 100644 --- a/device.c +++ b/device.c @@ -211,7 +211,7 @@ int device_claim(struct device_user *dep) return 0; dep->claimed = true; - D(DEVICE, "Claim %s %s, new refcount: %d\n", dev->type->name, dev->ifname, dev->active + 1); + D(DEVICE, "Claim %s %s, new active count: %d\n", dev->type->name, dev->ifname, dev->active + 1); if (++dev->active != 1) return 0; @@ -237,7 +237,7 @@ void device_release(struct device_user *dep) dep->claimed = false; dev->active--; - D(DEVICE, "Release %s %s, new refcount: %d\n", dev->type->name, dev->ifname, dev->active); + D(DEVICE, "Release %s %s, new active count: %d\n", dev->type->name, dev->ifname, dev->active); assert(dev->active >= 0); if (dev->active) @@ -394,6 +394,26 @@ void device_set_present(struct device *dev, bool state) device_refresh_present(dev); } +void device_set_link(struct device *dev, bool state) +{ + if (dev->link_active == state) + return; + + netifd_log_message(L_NOTICE, "%s '%s' link is %s\n", dev->type->name, dev->ifname, state ? "up" : "down" ); + + dev->link_active = state; + device_broadcast_event(dev, state ? DEV_EVENT_LINK_UP : DEV_EVENT_LINK_DOWN); +} + +void device_set_ifindex(struct device *dev, int ifindex) +{ + if (dev->ifindex == ifindex) + return; + + dev->ifindex = ifindex; + device_broadcast_event(dev, DEV_EVENT_UPDATE_IFINDEX); +} + static int device_refcount(struct device *dev) { struct list_head *list; @@ -435,6 +455,9 @@ void device_add_user(struct device_user *dep, struct device *dev) dep->cb(dep, DEV_EVENT_ADD); if (dev->active) dep->cb(dep, DEV_EVENT_UP); + + if (dev->link_active) + dep->cb(dep, DEV_EVENT_LINK_UP); } } @@ -667,6 +690,8 @@ device_dump_status(struct blob_buf *b, struct device *dev) return; blobmsg_add_u8(b, "up", !!dev->active); + blobmsg_add_u8(b, "carrier", !!dev->link_active); + if (dev->type->dump_info) dev->type->dump_info(dev, b); else diff --git a/device.h b/device.h index d63ffe3..dd57927 100644 --- a/device.h +++ b/device.h @@ -68,6 +68,7 @@ enum device_event { DEV_EVENT_REMOVE, DEV_EVENT_UPDATE_IFNAME, + DEV_EVENT_UPDATE_IFINDEX, DEV_EVENT_SETUP, DEV_EVENT_TEARDOWN, @@ -122,6 +123,7 @@ struct device { bool sys_present; bool present; int active; + bool link_active; bool external; bool disabled; @@ -178,6 +180,8 @@ void device_remove_user(struct device_user *dep); void device_broadcast_event(struct device *dev, enum device_event ev); void device_set_present(struct device *dev, bool state); +void device_set_link(struct device *dev, bool state); +void device_set_ifindex(struct device *dev, int ifindex); void device_refresh_present(struct device *dev); int device_claim(struct device_user *dep); void device_release(struct device_user *dep); diff --git a/system-linux.c b/system-linux.c index cbcc5bd..12682dc 100644 --- a/system-linux.c +++ b/system-linux.c @@ -58,7 +58,7 @@ struct event_socket { struct uloop_fd uloop; struct nl_sock *sock; - struct nl_cb *cb; + int bufsize; }; static int sock_ioctl = -1; @@ -73,7 +73,38 @@ static void handler_nl_event(struct uloop_fd *u, unsigned int events) { struct event_socket *ev = container_of(u, struct event_socket, uloop); - nl_recvmsgs(ev->sock, ev->cb); + int err; + socklen_t errlen = sizeof(err); + + if (!u->error) { + nl_recvmsgs_default(ev->sock); + return; + } + + if (getsockopt(u->fd, SOL_SOCKET, SO_ERROR, (void *)&err, &errlen)) + goto abort; + + switch(err) { + case ENOBUFS: + // Increase rx buffer size on netlink socket + ev->bufsize *= 2; + if (nl_socket_set_buffer_size(ev->sock, ev->bufsize, 0)) + goto abort; + + // Request full dump since some info got dropped + struct rtgenmsg msg = { .rtgen_family = AF_UNSPEC }; + nl_send_simple(ev->sock, RTM_GETLINK, NLM_F_DUMP, &msg, sizeof(msg)); + break; + + default: + goto abort; + } + u->error = false; + return; + +abort: + uloop_fd_delete(&ev->uloop); + return; } static struct nl_sock * @@ -96,7 +127,7 @@ create_socket(int protocol, int groups) static bool create_raw_event_socket(struct event_socket *ev, int protocol, int groups, - uloop_fd_handler cb) + uloop_fd_handler cb, int flags) { ev->sock = create_socket(protocol, groups); if (!ev->sock) @@ -104,7 +135,9 @@ create_raw_event_socket(struct event_socket *ev, int protocol, int groups, ev->uloop.fd = nl_socket_get_fd(ev->sock); ev->uloop.cb = cb; - uloop_fd_add(&ev->uloop, ULOOP_READ | ULOOP_EDGE_TRIGGER); + if (uloop_fd_add(&ev->uloop, ULOOP_READ|flags)) + return false; + return true; } @@ -112,14 +145,21 @@ static bool create_event_socket(struct event_socket *ev, int protocol, int (*cb)(struct nl_msg *msg, void *arg)) { - // Prepare socket for link events - ev->cb = nl_cb_alloc(NL_CB_DEFAULT); - if (!ev->cb) + if (!create_raw_event_socket(ev, protocol, 0, handler_nl_event, ULOOP_ERROR_CB)) return false; - nl_cb_set(ev->cb, NL_CB_VALID, NL_CB_CUSTOM, cb, NULL); + // Install the valid custom callback handler + nl_socket_modify_cb(ev->sock, NL_CB_VALID, NL_CB_CUSTOM, cb, NULL); + + // Disable sequence number checking on event sockets + nl_socket_disable_seq_check(ev->sock); - return create_raw_event_socket(ev, protocol, 0, handler_nl_event); + // Increase rx buffer size to 65K on event sockets + ev->bufsize = 65535; + if (nl_socket_set_buffer_size(ev->sock, ev->bufsize, 0)) + return false; + + return true; } int system_init(void) @@ -128,7 +168,7 @@ int system_init(void) static struct event_socket hotplug_event; sock_ioctl = socket(AF_LOCAL, SOCK_DGRAM, 0); - fcntl(sock_ioctl, F_SETFD, fcntl(sock_ioctl, F_GETFD) | FD_CLOEXEC); + system_fd_set_cloexec(sock_ioctl); // Prepare socket for routing / address control sock_rtnl = create_socket(NETLINK_ROUTE, 0); @@ -139,7 +179,7 @@ int system_init(void) return -1; if (!create_raw_event_socket(&hotplug_event, NETLINK_KOBJECT_UEVENT, 1, - handle_hotplug_event)) + handle_hotplug_event, 0)) return -1; // Receive network link events form kernel @@ -171,6 +211,10 @@ static void system_set_disable_ipv6(struct device *dev, const char *val) system_set_dev_sysctl("/proc/sys/net/ipv6/conf/%s/disable_ipv6", dev->ifname, val); } +#ifndef IFF_LOWER_UP +#define IFF_LOWER_UP 0x10000 +#endif + // Evaluate netlink messages static int cb_rtnl_event(struct nl_msg *msg, void *arg) { @@ -178,19 +222,19 @@ static int cb_rtnl_event(struct nl_msg *msg, void *arg) struct ifinfomsg *ifi = NLMSG_DATA(nh); struct nlattr *nla[__IFLA_MAX]; - if (nh->nlmsg_type != RTM_DELLINK && nh->nlmsg_type != RTM_NEWLINK) + if (nh->nlmsg_type != RTM_NEWLINK) goto out; nlmsg_parse(nh, sizeof(*ifi), nla, __IFLA_MAX - 1, NULL); if (!nla[IFLA_IFNAME]) goto out; - struct device *dev = device_get(RTA_DATA(nla[IFLA_IFNAME]), false); + struct device *dev = device_get(nla_data(nla[IFLA_IFNAME]), false); if (!dev) goto out; - dev->ifindex = ifi->ifi_index; - /* TODO: parse link status */ + device_set_ifindex(dev, ifi->ifi_index); + device_set_link(dev, ifi->ifi_flags & IFF_LOWER_UP ? true : false); out: return 0; @@ -538,7 +582,7 @@ void system_if_clear_state(struct device *dev) if (dev->external) return; - dev->ifindex = system_if_resolve(dev); + device_set_ifindex(dev, system_if_resolve(dev)); if (!dev->ifindex) return; @@ -782,7 +826,7 @@ int system_if_up(struct device *dev) { system_if_get_settings(dev, &dev->orig_settings); system_if_apply_settings(dev, &dev->settings); - dev->ifindex = system_if_resolve(dev); + device_set_ifindex(dev, system_if_resolve(dev)); return system_if_flags(dev->ifname, IFF_UP, 0); } @@ -794,10 +838,78 @@ int system_if_down(struct device *dev) return ret; } +struct if_check_data { + struct device *dev; + int pending; + int ret; +}; + +static int cb_if_check_valid(struct nl_msg *msg, void *arg) +{ + struct nlmsghdr *nh = nlmsg_hdr(msg); + struct ifinfomsg *ifi = NLMSG_DATA(nh); + struct if_check_data *chk = (struct if_check_data *)arg; + + if (nh->nlmsg_type != RTM_NEWLINK) + return NL_SKIP; + + device_set_present(chk->dev, ifi->ifi_index > 0 ? true : false); + device_set_link(chk->dev, ifi->ifi_flags & IFF_LOWER_UP ? true : false); + + return NL_OK; +} + +static int cb_if_check_ack(struct nl_msg *msg, void *arg) +{ + struct if_check_data *chk = (struct if_check_data *)arg; + chk->pending = 0; + return NL_STOP; +} + +static int cb_if_check_error(struct sockaddr_nl *nla, struct nlmsgerr *err, void *arg) +{ + struct if_check_data *chk = (struct if_check_data *)arg; + + device_set_present(chk->dev, false); + device_set_link(chk->dev, false); + chk->pending = err->error; + + return NL_STOP; +} + int system_if_check(struct device *dev) { - device_set_present(dev, (system_if_resolve(dev) > 0)); - return 0; + struct nl_cb *cb = nl_cb_alloc(NL_CB_DEFAULT); + struct nl_msg *msg; + struct ifinfomsg ifi = { + .ifi_family = AF_UNSPEC, + .ifi_index = 0, + }; + struct if_check_data chk = { + .dev = dev, + .pending = 1, + }; + int ret = 1; + + msg = nlmsg_alloc_simple(RTM_GETLINK, 0); + if (!msg || nlmsg_append(msg, &ifi, sizeof(ifi), 0) || + nla_put_string(msg, IFLA_IFNAME, dev->ifname)) + goto out; + + nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, cb_if_check_valid, &chk); + nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, cb_if_check_ack, &chk); + nl_cb_err(cb, NL_CB_CUSTOM, cb_if_check_error, &chk); + + nl_send_auto_complete(sock_rtnl, msg); + while (chk.pending > 0) + nl_recvmsgs(sock_rtnl, cb); + + nlmsg_free(msg); + ret = chk.pending; + +out: + nl_cb_put(cb); + return ret; } struct device * @@ -915,14 +1027,10 @@ system_if_dump_info(struct device *dev, struct blob_buf *b) char buf[64], *s; void *c; int dir_fd; - uint64_t val = 0; snprintf(buf, sizeof(buf), "/sys/class/net/%s", dev->ifname); dir_fd = open(buf, O_DIRECTORY); - if (read_uint64_file(dir_fd, "carrier", &val)) - blobmsg_add_u8(b, "link", !!val); - memset(&ecmd, 0, sizeof(ecmd)); memset(&ifr, 0, sizeof(ifr)); strcpy(ifr.ifr_name, dev->ifname); -- 2.25.1