/* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Routing netlink socket interface: protocol independent part. * * Authors: Alexey Kuznetsov, * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Fixes: * Vitaly E. Lavrov RTA_OK arithmetics was wrong. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include DECLARE_MUTEX(rtnl_sem); void rtnl_lock(void) { rtnl_shlock(); } int rtnl_lock_interruptible(void) { return down_interruptible(&rtnl_sem); } void rtnl_unlock(void) { rtnl_shunlock(); netdev_run_todo(); } int rtattr_parse(struct rtattr *tb[], int maxattr, struct rtattr *rta, int len) { memset(tb, 0, sizeof(struct rtattr*)*maxattr); while (RTA_OK(rta, len)) { unsigned flavor = rta->rta_type; if (flavor && flavor <= maxattr) tb[flavor-1] = rta; rta = RTA_NEXT(rta, len); } return 0; } struct sock *rtnl; struct rtnetlink_link * rtnetlink_links[NPROTO]; static const int rtm_min[RTM_NR_FAMILIES] = { [RTM_FAM(RTM_NEWLINK)] = NLMSG_LENGTH(sizeof(struct ifinfomsg)), [RTM_FAM(RTM_NEWADDR)] = NLMSG_LENGTH(sizeof(struct ifaddrmsg)), [RTM_FAM(RTM_NEWROUTE)] = NLMSG_LENGTH(sizeof(struct rtmsg)), [RTM_FAM(RTM_NEWNEIGH)] = NLMSG_LENGTH(sizeof(struct ndmsg)), [RTM_FAM(RTM_NEWRULE)] = NLMSG_LENGTH(sizeof(struct rtmsg)), [RTM_FAM(RTM_NEWQDISC)] = NLMSG_LENGTH(sizeof(struct tcmsg)), [RTM_FAM(RTM_NEWTCLASS)] = NLMSG_LENGTH(sizeof(struct tcmsg)), [RTM_FAM(RTM_NEWTFILTER)] = NLMSG_LENGTH(sizeof(struct tcmsg)), [RTM_FAM(RTM_NEWACTION)] = NLMSG_LENGTH(sizeof(struct tcamsg)), [RTM_FAM(RTM_NEWPREFIX)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)), [RTM_FAM(RTM_GETMULTICAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)), [RTM_FAM(RTM_GETANYCAST)] = NLMSG_LENGTH(sizeof(struct rtgenmsg)), [RTM_FAM(RTM_NEWNEIGHTBL)] = NLMSG_LENGTH(sizeof(struct ndtmsg)), }; static const int rta_max[RTM_NR_FAMILIES] = { [RTM_FAM(RTM_NEWLINK)] = IFLA_MAX, [RTM_FAM(RTM_NEWADDR)] = IFA_MAX, [RTM_FAM(RTM_NEWROUTE)] = RTA_MAX, [RTM_FAM(RTM_NEWNEIGH)] = NDA_MAX, [RTM_FAM(RTM_NEWRULE)] = RTA_MAX, [RTM_FAM(RTM_NEWQDISC)] = TCA_MAX, [RTM_FAM(RTM_NEWTCLASS)] = TCA_MAX, [RTM_FAM(RTM_NEWTFILTER)] = TCA_MAX, [RTM_FAM(RTM_NEWACTION)] = TCAA_MAX, [RTM_FAM(RTM_NEWNEIGHTBL)] = NDTA_MAX, }; void __rta_fill(struct sk_buff *skb, int attrtype, int attrlen, const void *data) { struct rtattr *rta; int size = RTA_LENGTH(attrlen); rta = (struct rtattr*)skb_put(skb, RTA_ALIGN(size)); rta->rta_type = attrtype; rta->rta_len = size; memcpy(RTA_DATA(rta), data, attrlen); memset(RTA_DATA(rta) + attrlen, 0, RTA_ALIGN(size) - size); } size_t rtattr_strlcpy(char *dest, const struct rtattr *rta, size_t size) { size_t ret = RTA_PAYLOAD(rta); char *src = RTA_DATA(rta); if (ret > 0 && src[ret - 1] == '\0') ret--; if (size > 0) { size_t len = (ret >= size) ? size - 1 : ret; memset(dest, 0, size); memcpy(dest, src, len); } return ret; } int rtnetlink_send(struct sk_buff *skb, u32 pid, unsigned group, int echo) { int err = 0; NETLINK_CB(skb).dst_group = group; if (echo) atomic_inc(&skb->users); netlink_broadcast(rtnl, skb, pid, group, GFP_KERNEL); if (echo) err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT); return err; } int rtnetlink_put_metrics(struct sk_buff *skb, u32 *metrics) { struct rtattr *mx = (struct rtattr*)skb->tail; int i; RTA_PUT(skb, RTA_METRICS, 0, NULL); for (i=0; irta_len = skb->tail - (u8*)mx; if (mx->rta_len == RTA_LENGTH(0)) skb_trim(skb, (u8*)mx - skb->data); return 0; rtattr_failure: skb_trim(skb, (u8*)mx - skb->data); return -1; } static int rtnetlink_fill_ifinfo(struct sk_buff *skb, struct net_device *dev, int type, u32 pid, u32 seq, u32 change, unsigned int flags) { struct ifinfomsg *r; struct nlmsghdr *nlh; unsigned char *b = skb->tail; nlh = NLMSG_NEW(skb, pid, seq, type, sizeof(*r), flags); r = NLMSG_DATA(nlh); r->ifi_family = AF_UNSPEC; r->__ifi_pad = 0; r->ifi_type = dev->type; r->ifi_index = dev->ifindex; r->ifi_flags = dev_get_flags(dev); r->ifi_change = change; RTA_PUT(skb, IFLA_IFNAME, strlen(dev->name)+1, dev->name); if (1) { u32 txqlen = dev->tx_queue_len; RTA_PUT(skb, IFLA_TXQLEN, sizeof(txqlen), &txqlen); } if (1) { u32 weight = dev->weight; RTA_PUT(skb, IFLA_WEIGHT, sizeof(weight), &weight); } if (1) { struct rtnl_link_ifmap map = { .mem_start = dev->mem_start, .mem_end = dev->mem_end, .base_addr = dev->base_addr, .irq = dev->irq, .dma = dev->dma, .port = dev->if_port, }; RTA_PUT(skb, IFLA_MAP, sizeof(map), &map); } if (dev->addr_len) { RTA_PUT(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr); RTA_PUT(skb, IFLA_BROADCAST, dev->addr_len, dev->broadcast); } if (1) { u32 mtu = dev->mtu; RTA_PUT(skb, IFLA_MTU, sizeof(mtu), &mtu); } if (dev->ifindex != dev->iflink) { u32 iflink = dev->iflink; RTA_PUT(skb, IFLA_LINK, sizeof(iflink), &iflink); } if (dev->qdisc_sleeping) RTA_PUT(skb, IFLA_QDISC, strlen(dev->qdisc_sleeping->ops->id) + 1, dev->qdisc_sleeping->ops->id); if (dev->master) { u32 master = dev->master->ifindex; RTA_PUT(skb, IFLA_MASTER, sizeof(master), &master); } if (dev->get_stats) { unsigned long *stats = (unsigned long*)dev->get_stats(dev); if (stats) { struct rtattr *a; __u32 *s; int i; int n = sizeof(struct rtnl_link_stats)/4; a = __RTA_PUT(skb, IFLA_STATS, n*4); s = RTA_DATA(a); for (i=0; inlmsg_len = skb->tail - b; return skb->len; nlmsg_failure: rtattr_failure: skb_trim(skb, b - skb->data); return -1; } static int rtnetlink_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb) { int idx; int s_idx = cb->args[0]; struct net_device *dev; read_lock(&dev_base_lock); for (dev=dev_base, idx=0; dev; dev = dev->next, idx++) { if (idx < s_idx) continue; if (rtnetlink_fill_ifinfo(skb, dev, RTM_NEWLINK, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq, 0, NLM_F_MULTI) <= 0) break; } read_unlock(&dev_base_lock); cb->args[0] = idx; return skb->len; } static int do_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg) { struct ifinfomsg *ifm = NLMSG_DATA(nlh); struct rtattr **ida = arg; struct net_device *dev; int err, send_addr_notify = 0; if (ifm->ifi_index >= 0) dev = dev_get_by_index(ifm->ifi_index); else if (ida[IFLA_IFNAME - 1]) { char ifname[IFNAMSIZ]; if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1], IFNAMSIZ) >= IFNAMSIZ) return -EINVAL; dev = dev_get_by_name(ifname); } else return -EINVAL; if (!dev) return -ENODEV; err = -EINVAL; if (ifm->ifi_flags) dev_change_flags(dev, ifm->ifi_flags); if (ida[IFLA_MAP - 1]) { struct rtnl_link_ifmap *u_map; struct ifmap k_map; if (!dev->set_config) { err = -EOPNOTSUPP; goto out; } if (!netif_device_present(dev)) { err = -ENODEV; goto out; } if (ida[IFLA_MAP - 1]->rta_len != RTA_LENGTH(sizeof(*u_map))) goto out; u_map = RTA_DATA(ida[IFLA_MAP - 1]); k_map.mem_start = (unsigned long) u_map->mem_start; k_map.mem_end = (unsigned long) u_map->mem_end; k_map.base_addr = (unsigned short) u_map->base_addr; k_map.irq = (unsigned char) u_map->irq; k_map.dma = (unsigned char) u_map->dma; k_map.port = (unsigned char) u_map->port; err = dev->set_config(dev, &k_map); if (err) goto out; } if (ida[IFLA_ADDRESS - 1]) { if (!dev->set_mac_address) { err = -EOPNOTSUPP; goto out; } if (!netif_device_present(dev)) { err = -ENODEV; goto out; } if (ida[IFLA_ADDRESS - 1]->rta_len != RTA_LENGTH(dev->addr_len)) goto out; err = dev->set_mac_address(dev, RTA_DATA(ida[IFLA_ADDRESS - 1])); if (err) goto out; send_addr_notify = 1; } if (ida[IFLA_BROADCAST - 1]) { if (ida[IFLA_BROADCAST - 1]->rta_len != RTA_LENGTH(dev->addr_len)) goto out; memcpy(dev->broadcast, RTA_DATA(ida[IFLA_BROADCAST - 1]), dev->addr_len); send_addr_notify = 1; } if (ida[IFLA_MTU - 1]) { if (ida[IFLA_MTU - 1]->rta_len != RTA_LENGTH(sizeof(u32))) goto out; err = dev_set_mtu(dev, *((u32 *) RTA_DATA(ida[IFLA_MTU - 1]))); if (err) goto out; } if (ida[IFLA_TXQLEN - 1]) { if (ida[IFLA_TXQLEN - 1]->rta_len != RTA_LENGTH(sizeof(u32))) goto out; dev->tx_queue_len = *((u32 *) RTA_DATA(ida[IFLA_TXQLEN - 1])); } if (ida[IFLA_WEIGHT - 1]) { if (ida[IFLA_WEIGHT - 1]->rta_len != RTA_LENGTH(sizeof(u32))) goto out; dev->weight = *((u32 *) RTA_DATA(ida[IFLA_WEIGHT - 1])); } if (ifm->ifi_index >= 0 && ida[IFLA_IFNAME - 1]) { char ifname[IFNAMSIZ]; if (rtattr_strlcpy(ifname, ida[IFLA_IFNAME - 1], IFNAMSIZ) >= IFNAMSIZ) goto out; err = dev_change_name(dev, ifname); if (err) goto out; } err = 0; out: if (send_addr_notify) call_netdevice_notifiers(NETDEV_CHANGEADDR, dev); dev_put(dev); return err; } static int rtnetlink_dump_all(struct sk_buff *skb, struct netlink_callback *cb) { int idx; int s_idx = cb->family; if (s_idx == 0) s_idx = 1; for (idx=1; idxnlh->nlmsg_type-RTM_BASE; if (idx < s_idx || idx == PF_PACKET) continue; if (rtnetlink_links[idx] == NULL || rtnetlink_links[idx][type].dumpit == NULL) continue; if (idx > s_idx) memset(&cb->args[0], 0, sizeof(cb->args)); if (rtnetlink_links[idx][type].dumpit(skb, cb)) break; } cb->family = idx; return skb->len; } void rtmsg_ifinfo(int type, struct net_device *dev, unsigned change) { struct sk_buff *skb; int size = NLMSG_SPACE(sizeof(struct ifinfomsg) + sizeof(struct rtnl_link_ifmap) + sizeof(struct rtnl_link_stats) + 128); skb = alloc_skb(size, GFP_KERNEL); if (!skb) return; if (rtnetlink_fill_ifinfo(skb, dev, type, current->pid, 0, change, 0) < 0) { kfree_skb(skb); return; } NETLINK_CB(skb).dst_group = RTNLGRP_LINK; netlink_broadcast(rtnl, skb, 0, RTNLGRP_LINK, GFP_KERNEL); } static int rtnetlink_done(struct netlink_callback *cb) { return 0; } /* Protected by RTNL sempahore. */ static struct rtattr **rta_buf; static int rtattr_max; /* Process one rtnetlink message. */ static __inline__ int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, int *errp) { struct rtnetlink_link *link; struct rtnetlink_link *link_tab; int sz_idx, kind; int min_len; int family; int type; int err; /* Only requests are handled by kernel now */ if (!(nlh->nlmsg_flags&NLM_F_REQUEST)) return 0; type = nlh->nlmsg_type; /* A control message: ignore them */ if (type < RTM_BASE) return 0; /* Unknown message: reply with EINVAL */ if (type > RTM_MAX) goto err_inval; type -= RTM_BASE; /* All the messages must have at least 1 byte length */ if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct rtgenmsg))) return 0; family = ((struct rtgenmsg*)NLMSG_DATA(nlh))->rtgen_family; if (family >= NPROTO) { *errp = -EAFNOSUPPORT; return -1; } link_tab = rtnetlink_links[family]; if (link_tab == NULL) link_tab = rtnetlink_links[PF_UNSPEC]; link = &link_tab[type]; sz_idx = type>>2; kind = type&3; if (kind != 2 && security_netlink_recv(skb)) { *errp = -EPERM; return -1; } if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) { u32 rlen; if (link->dumpit == NULL) link = &(rtnetlink_links[PF_UNSPEC][type]); if (link->dumpit == NULL) goto err_inval; if ((*errp = netlink_dump_start(rtnl, skb, nlh, link->dumpit, rtnetlink_done)) != 0) { return -1; } rlen = NLMSG_ALIGN(nlh->nlmsg_len); if (rlen > skb->len) rlen = skb->len; skb_pull(skb, rlen); return -1; } memset(rta_buf, 0, (rtattr_max * sizeof(struct rtattr *))); min_len = rtm_min[sz_idx]; if (nlh->nlmsg_len < min_len) goto err_inval; if (nlh->nlmsg_len > min_len) { int attrlen = nlh->nlmsg_len - NLMSG_ALIGN(min_len); struct rtattr *attr = (void*)nlh + NLMSG_ALIGN(min_len); while (RTA_OK(attr, attrlen)) { unsigned flavor = attr->rta_type; if (flavor) { if (flavor > rta_max[sz_idx]) goto err_inval; rta_buf[flavor-1] = attr; } attr = RTA_NEXT(attr, attrlen); } } if (link->doit == NULL) link = &(rtnetlink_links[PF_UNSPEC][type]); if (link->doit == NULL) goto err_inval; err = link->doit(skb, nlh, (void *)&rta_buf[0]); *errp = err; return err; err_inval: *errp = -EINVAL; return -1; } /* * Process one packet of messages. * Malformed skbs with wrong lengths of messages are discarded silently. */ static inline int rtnetlink_rcv_skb(struct sk_buff *skb) { int err; struct nlmsghdr * nlh; while (skb->len >= NLMSG_SPACE(0)) { u32 rlen; nlh = (struct nlmsghdr *)skb->data; if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len) return 0; rlen = NLMSG_ALIGN(nlh->nlmsg_len); if (rlen > skb->len) rlen = skb->len; if (rtnetlink_rcv_msg(skb, nlh, &err)) { /* Not error, but we must interrupt processing here: * Note, that in this case we do not pull message * from skb, it will be processed later. */ if (err == 0) return -1; netlink_ack(skb, nlh, err); } else if (nlh->nlmsg_flags&NLM_F_ACK) netlink_ack(skb, nlh, 0); skb_pull(skb, rlen); } return 0; } /* * rtnetlink input queue processing routine: * - process as much as there was in the queue upon entry. * - feed skbs to rtnetlink_rcv_skb, until it refuse a message, * that will occur, when a dump started. */ static void rtnetlink_rcv(struct sock *sk, int len) { unsigned int qlen = skb_queue_len(&sk->sk_receive_queue); do { struct sk_buff *skb; rtnl_lock(); if (qlen > skb_queue_len(&sk->sk_receive_queue)) qlen = skb_queue_len(&sk->sk_receive_queue); for (; qlen; qlen--) { skb = skb_dequeue(&sk->sk_receive_queue); if (rtnetlink_rcv_skb(skb)) { if (skb->len) skb_queue_head(&sk->sk_receive_queue, skb); else { kfree_skb(skb); qlen--; } break; } kfree_skb(skb); } up(&rtnl_sem); netdev_run_todo(); } while (qlen); } static struct rtnetlink_link link_rtnetlink_table[RTM_NR_MSGTYPES] = { [RTM_GETLINK - RTM_BASE] = { .dumpit = rtnetlink_dump_ifinfo }, [RTM_SETLINK - RTM_BASE] = { .doit = do_setlink }, [RTM_GETADDR - RTM_BASE] = { .dumpit = rtnetlink_dump_all }, [RTM_GETROUTE - RTM_BASE] = { .dumpit = rtnetlink_dump_all }, [RTM_NEWNEIGH - RTM_BASE] = { .doit = neigh_add }, [RTM_DELNEIGH - RTM_BASE] = { .doit = neigh_delete }, [RTM_GETNEIGH - RTM_BASE] = { .dumpit = neigh_dump_info }, [RTM_GETRULE - RTM_BASE] = { .dumpit = rtnetlink_dump_all }, [RTM_GETNEIGHTBL - RTM_BASE] = { .dumpit = neightbl_dump_info }, [RTM_SETNEIGHTBL - RTM_BASE] = { .doit = neightbl_set }, }; static int rtnetlink_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = ptr; switch (event) { case NETDEV_UNREGISTER: rtmsg_ifinfo(RTM_DELLINK, dev, ~0U); break; case NETDEV_REGISTER: rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U); break; case NETDEV_UP: case NETDEV_DOWN: rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING); break; case NETDEV_CHANGE: case NETDEV_GOING_DOWN: break; default: rtmsg_ifinfo(RTM_NEWLINK, dev, 0); break; } return NOTIFY_DONE; } static struct notifier_block rtnetlink_dev_notifier = { .notifier_call = rtnetlink_event, }; void __init rtnetlink_init(void) { int i; rtattr_max = 0; for (i = 0; i < ARRAY_SIZE(rta_max); i++) if (rta_max[i] > rtattr_max) rtattr_max = rta_max[i]; rta_buf = kmalloc(rtattr_max * sizeof(struct rtattr *), GFP_KERNEL); if (!rta_buf) panic("rtnetlink_init: cannot allocate rta_buf\n"); rtnl = netlink_kernel_create(NETLINK_ROUTE, RTNLGRP_MAX, rtnetlink_rcv, THIS_MODULE); if (rtnl == NULL) panic("rtnetlink_init: cannot initialize rtnetlink\n"); netlink_set_nonroot(NETLINK_ROUTE, NL_NONROOT_RECV); register_netdevice_notifier(&rtnetlink_dev_notifier); rtnetlink_links[PF_UNSPEC] = link_rtnetlink_table; rtnetlink_links[PF_PACKET] = link_rtnetlink_table; } EXPORT_SYMBOL(__rta_fill); EXPORT_SYMBOL(rtattr_strlcpy); EXPORT_SYMBOL(rtattr_parse); EXPORT_SYMBOL(rtnetlink_links); EXPORT_SYMBOL(rtnetlink_put_metrics); EXPORT_SYMBOL(rtnl); EXPORT_SYMBOL(rtnl_lock); EXPORT_SYMBOL(rtnl_lock_interruptible); EXPORT_SYMBOL(rtnl_sem); EXPORT_SYMBOL(rtnl_unlock);