| /* |
| * 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. |
| * |
| * IPv4 Forwarding Information Base: FIB frontend. |
| * |
| * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> |
| * |
| * 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. |
| */ |
| |
| #include <linux/module.h> |
| #include <asm/uaccess.h> |
| #include <linux/bitops.h> |
| #include <linux/capability.h> |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/string.h> |
| #include <linux/socket.h> |
| #include <linux/sockios.h> |
| #include <linux/errno.h> |
| #include <linux/in.h> |
| #include <linux/inet.h> |
| #include <linux/inetdevice.h> |
| #include <linux/netdevice.h> |
| #include <linux/if_addr.h> |
| #include <linux/if_arp.h> |
| #include <linux/skbuff.h> |
| #include <linux/cache.h> |
| #include <linux/init.h> |
| #include <linux/list.h> |
| #include <linux/slab.h> |
| |
| #include <net/ip.h> |
| #include <net/protocol.h> |
| #include <net/route.h> |
| #include <net/tcp.h> |
| #include <net/sock.h> |
| #include <net/arp.h> |
| #include <net/ip_fib.h> |
| #include <net/rtnetlink.h> |
| #include <net/xfrm.h> |
| #include <net/l3mdev.h> |
| #include <net/lwtunnel.h> |
| #include <trace/events/fib.h> |
| |
| #ifndef CONFIG_IP_MULTIPLE_TABLES |
| |
| static int __net_init fib4_rules_init(struct net *net) |
| { |
| struct fib_table *local_table, *main_table; |
| |
| main_table = fib_trie_table(RT_TABLE_MAIN, NULL); |
| if (!main_table) |
| return -ENOMEM; |
| |
| local_table = fib_trie_table(RT_TABLE_LOCAL, main_table); |
| if (!local_table) |
| goto fail; |
| |
| hlist_add_head_rcu(&local_table->tb_hlist, |
| &net->ipv4.fib_table_hash[TABLE_LOCAL_INDEX]); |
| hlist_add_head_rcu(&main_table->tb_hlist, |
| &net->ipv4.fib_table_hash[TABLE_MAIN_INDEX]); |
| return 0; |
| |
| fail: |
| fib_free_table(main_table); |
| return -ENOMEM; |
| } |
| #else |
| |
| struct fib_table *fib_new_table(struct net *net, u32 id) |
| { |
| struct fib_table *tb, *alias = NULL; |
| unsigned int h; |
| |
| if (id == 0) |
| id = RT_TABLE_MAIN; |
| tb = fib_get_table(net, id); |
| if (tb) |
| return tb; |
| |
| if (id == RT_TABLE_LOCAL && !net->ipv4.fib_has_custom_rules) |
| alias = fib_new_table(net, RT_TABLE_MAIN); |
| |
| tb = fib_trie_table(id, alias); |
| if (!tb) |
| return NULL; |
| |
| switch (id) { |
| case RT_TABLE_MAIN: |
| rcu_assign_pointer(net->ipv4.fib_main, tb); |
| break; |
| case RT_TABLE_DEFAULT: |
| rcu_assign_pointer(net->ipv4.fib_default, tb); |
| break; |
| default: |
| break; |
| } |
| |
| h = id & (FIB_TABLE_HASHSZ - 1); |
| hlist_add_head_rcu(&tb->tb_hlist, &net->ipv4.fib_table_hash[h]); |
| return tb; |
| } |
| EXPORT_SYMBOL_GPL(fib_new_table); |
| |
| /* caller must hold either rtnl or rcu read lock */ |
| struct fib_table *fib_get_table(struct net *net, u32 id) |
| { |
| struct fib_table *tb; |
| struct hlist_head *head; |
| unsigned int h; |
| |
| if (id == 0) |
| id = RT_TABLE_MAIN; |
| h = id & (FIB_TABLE_HASHSZ - 1); |
| |
| head = &net->ipv4.fib_table_hash[h]; |
| hlist_for_each_entry_rcu(tb, head, tb_hlist) { |
| if (tb->tb_id == id) |
| return tb; |
| } |
| return NULL; |
| } |
| #endif /* CONFIG_IP_MULTIPLE_TABLES */ |
| |
| static void fib_replace_table(struct net *net, struct fib_table *old, |
| struct fib_table *new) |
| { |
| #ifdef CONFIG_IP_MULTIPLE_TABLES |
| switch (new->tb_id) { |
| case RT_TABLE_MAIN: |
| rcu_assign_pointer(net->ipv4.fib_main, new); |
| break; |
| case RT_TABLE_DEFAULT: |
| rcu_assign_pointer(net->ipv4.fib_default, new); |
| break; |
| default: |
| break; |
| } |
| |
| #endif |
| /* replace the old table in the hlist */ |
| hlist_replace_rcu(&old->tb_hlist, &new->tb_hlist); |
| } |
| |
| int fib_unmerge(struct net *net) |
| { |
| struct fib_table *old, *new, *main_table; |
| |
| /* attempt to fetch local table if it has been allocated */ |
| old = fib_get_table(net, RT_TABLE_LOCAL); |
| if (!old) |
| return 0; |
| |
| new = fib_trie_unmerge(old); |
| if (!new) |
| return -ENOMEM; |
| |
| /* table is already unmerged */ |
| if (new == old) |
| return 0; |
| |
| /* replace merged table with clean table */ |
| fib_replace_table(net, old, new); |
| fib_free_table(old); |
| |
| /* attempt to fetch main table if it has been allocated */ |
| main_table = fib_get_table(net, RT_TABLE_MAIN); |
| if (!main_table) |
| return 0; |
| |
| /* flush local entries from main table */ |
| fib_table_flush_external(main_table); |
| |
| return 0; |
| } |
| |
| static void fib_flush(struct net *net) |
| { |
| int flushed = 0; |
| unsigned int h; |
| |
| for (h = 0; h < FIB_TABLE_HASHSZ; h++) { |
| struct hlist_head *head = &net->ipv4.fib_table_hash[h]; |
| struct hlist_node *tmp; |
| struct fib_table *tb; |
| |
| hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) |
| flushed += fib_table_flush(net, tb); |
| } |
| |
| if (flushed) |
| rt_cache_flush(net); |
| } |
| |
| /* |
| * Find address type as if only "dev" was present in the system. If |
| * on_dev is NULL then all interfaces are taken into consideration. |
| */ |
| static inline unsigned int __inet_dev_addr_type(struct net *net, |
| const struct net_device *dev, |
| __be32 addr, u32 tb_id) |
| { |
| struct flowi4 fl4 = { .daddr = addr }; |
| struct fib_result res; |
| unsigned int ret = RTN_BROADCAST; |
| struct fib_table *table; |
| |
| if (ipv4_is_zeronet(addr) || ipv4_is_lbcast(addr)) |
| return RTN_BROADCAST; |
| if (ipv4_is_multicast(addr)) |
| return RTN_MULTICAST; |
| |
| rcu_read_lock(); |
| |
| table = fib_get_table(net, tb_id); |
| if (table) { |
| ret = RTN_UNICAST; |
| if (!fib_table_lookup(table, &fl4, &res, FIB_LOOKUP_NOREF)) { |
| if (!dev || dev == res.fi->fib_dev) |
| ret = res.type; |
| } |
| } |
| |
| rcu_read_unlock(); |
| return ret; |
| } |
| |
| unsigned int inet_addr_type_table(struct net *net, __be32 addr, u32 tb_id) |
| { |
| return __inet_dev_addr_type(net, NULL, addr, tb_id); |
| } |
| EXPORT_SYMBOL(inet_addr_type_table); |
| |
| unsigned int inet_addr_type(struct net *net, __be32 addr) |
| { |
| return __inet_dev_addr_type(net, NULL, addr, RT_TABLE_LOCAL); |
| } |
| EXPORT_SYMBOL(inet_addr_type); |
| |
| unsigned int inet_dev_addr_type(struct net *net, const struct net_device *dev, |
| __be32 addr) |
| { |
| u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL; |
| |
| return __inet_dev_addr_type(net, dev, addr, rt_table); |
| } |
| EXPORT_SYMBOL(inet_dev_addr_type); |
| |
| /* inet_addr_type with dev == NULL but using the table from a dev |
| * if one is associated |
| */ |
| unsigned int inet_addr_type_dev_table(struct net *net, |
| const struct net_device *dev, |
| __be32 addr) |
| { |
| u32 rt_table = l3mdev_fib_table(dev) ? : RT_TABLE_LOCAL; |
| |
| return __inet_dev_addr_type(net, NULL, addr, rt_table); |
| } |
| EXPORT_SYMBOL(inet_addr_type_dev_table); |
| |
| __be32 fib_compute_spec_dst(struct sk_buff *skb) |
| { |
| struct net_device *dev = skb->dev; |
| struct in_device *in_dev; |
| struct fib_result res; |
| struct rtable *rt; |
| struct net *net; |
| int scope; |
| |
| rt = skb_rtable(skb); |
| if ((rt->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST | RTCF_LOCAL)) == |
| RTCF_LOCAL) |
| return ip_hdr(skb)->daddr; |
| |
| in_dev = __in_dev_get_rcu(dev); |
| BUG_ON(!in_dev); |
| |
| net = dev_net(dev); |
| |
| scope = RT_SCOPE_UNIVERSE; |
| if (!ipv4_is_zeronet(ip_hdr(skb)->saddr)) { |
| struct flowi4 fl4 = { |
| .flowi4_iif = LOOPBACK_IFINDEX, |
| .daddr = ip_hdr(skb)->saddr, |
| .flowi4_tos = RT_TOS(ip_hdr(skb)->tos), |
| .flowi4_scope = scope, |
| .flowi4_mark = IN_DEV_SRC_VMARK(in_dev) ? skb->mark : 0, |
| }; |
| if (!fib_lookup(net, &fl4, &res, 0)) |
| return FIB_RES_PREFSRC(net, res); |
| } else { |
| scope = RT_SCOPE_LINK; |
| } |
| |
| return inet_select_addr(dev, ip_hdr(skb)->saddr, scope); |
| } |
| |
| /* Given (packet source, input interface) and optional (dst, oif, tos): |
| * - (main) check, that source is valid i.e. not broadcast or our local |
| * address. |
| * - figure out what "logical" interface this packet arrived |
| * and calculate "specific destination" address. |
| * - check, that packet arrived from expected physical interface. |
| * called with rcu_read_lock() |
| */ |
| static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, |
| u8 tos, int oif, struct net_device *dev, |
| int rpf, struct in_device *idev, u32 *itag) |
| { |
| int ret, no_addr; |
| struct fib_result res; |
| struct flowi4 fl4; |
| struct net *net; |
| bool dev_match; |
| |
| fl4.flowi4_oif = 0; |
| fl4.flowi4_iif = l3mdev_master_ifindex_rcu(dev); |
| if (!fl4.flowi4_iif) |
| fl4.flowi4_iif = oif ? : LOOPBACK_IFINDEX; |
| fl4.daddr = src; |
| fl4.saddr = dst; |
| fl4.flowi4_tos = tos; |
| fl4.flowi4_scope = RT_SCOPE_UNIVERSE; |
| fl4.flowi4_tun_key.tun_id = 0; |
| fl4.flowi4_flags = 0; |
| |
| no_addr = idev->ifa_list == NULL; |
| |
| fl4.flowi4_mark = IN_DEV_SRC_VMARK(idev) ? skb->mark : 0; |
| |
| trace_fib_validate_source(dev, &fl4); |
| |
| net = dev_net(dev); |
| if (fib_lookup(net, &fl4, &res, 0)) |
| goto last_resort; |
| if (res.type != RTN_UNICAST && |
| (res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev))) |
| goto e_inval; |
| if (!rpf && !fib_num_tclassid_users(dev_net(dev)) && |
| (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) |
| goto last_resort; |
| fib_combine_itag(itag, &res); |
| dev_match = false; |
| |
| #ifdef CONFIG_IP_ROUTE_MULTIPATH |
| for (ret = 0; ret < res.fi->fib_nhs; ret++) { |
| struct fib_nh *nh = &res.fi->fib_nh[ret]; |
| |
| if (nh->nh_dev == dev) { |
| dev_match = true; |
| break; |
| } else if (l3mdev_master_ifindex_rcu(nh->nh_dev) == dev->ifindex) { |
| dev_match = true; |
| break; |
| } |
| } |
| #else |
| if (FIB_RES_DEV(res) == dev) |
| dev_match = true; |
| #endif |
| if (dev_match) { |
| ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; |
| return ret; |
| } |
| if (no_addr) |
| goto last_resort; |
| if (rpf == 1) |
| goto e_rpf; |
| fl4.flowi4_oif = dev->ifindex; |
| |
| ret = 0; |
| if (fib_lookup(net, &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE) == 0) { |
| if (res.type == RTN_UNICAST) |
| ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST; |
| } |
| return ret; |
| |
| last_resort: |
| if (rpf) |
| goto e_rpf; |
| *itag = 0; |
| return 0; |
| |
| e_inval: |
| return -EINVAL; |
| e_rpf: |
| return -EXDEV; |
| } |
| |
| /* Ignore rp_filter for packets protected by IPsec. */ |
| int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst, |
| u8 tos, int oif, struct net_device *dev, |
| struct in_device *idev, u32 *itag) |
| { |
| int r = secpath_exists(skb) ? 0 : IN_DEV_RPFILTER(idev); |
| |
| if (!r && !fib_num_tclassid_users(dev_net(dev)) && |
| IN_DEV_ACCEPT_LOCAL(idev) && |
| (dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) { |
| *itag = 0; |
| return 0; |
| } |
| return __fib_validate_source(skb, src, dst, tos, oif, dev, r, idev, itag); |
| } |
| |
| static inline __be32 sk_extract_addr(struct sockaddr *addr) |
| { |
| return ((struct sockaddr_in *) addr)->sin_addr.s_addr; |
| } |
| |
| static int put_rtax(struct nlattr *mx, int len, int type, u32 value) |
| { |
| struct nlattr *nla; |
| |
| nla = (struct nlattr *) ((char *) mx + len); |
| nla->nla_type = type; |
| nla->nla_len = nla_attr_size(4); |
| *(u32 *) nla_data(nla) = value; |
| |
| return len + nla_total_size(4); |
| } |
| |
| static int rtentry_to_fib_config(struct net *net, int cmd, struct rtentry *rt, |
| struct fib_config *cfg) |
| { |
| __be32 addr; |
| int plen; |
| |
| memset(cfg, 0, sizeof(*cfg)); |
| cfg->fc_nlinfo.nl_net = net; |
| |
| if (rt->rt_dst.sa_family != AF_INET) |
| return -EAFNOSUPPORT; |
| |
| /* |
| * Check mask for validity: |
| * a) it must be contiguous. |
| * b) destination must have all host bits clear. |
| * c) if application forgot to set correct family (AF_INET), |
| * reject request unless it is absolutely clear i.e. |
| * both family and mask are zero. |
| */ |
| plen = 32; |
| addr = sk_extract_addr(&rt->rt_dst); |
| if (!(rt->rt_flags & RTF_HOST)) { |
| __be32 mask = sk_extract_addr(&rt->rt_genmask); |
| |
| if (rt->rt_genmask.sa_family != AF_INET) { |
| if (mask || rt->rt_genmask.sa_family) |
| return -EAFNOSUPPORT; |
| } |
| |
| if (bad_mask(mask, addr)) |
| return -EINVAL; |
| |
| plen = inet_mask_len(mask); |
| } |
| |
| cfg->fc_dst_len = plen; |
| cfg->fc_dst = addr; |
| |
| if (cmd != SIOCDELRT) { |
| cfg->fc_nlflags = NLM_F_CREATE; |
| cfg->fc_protocol = RTPROT_BOOT; |
| } |
| |
| if (rt->rt_metric) |
| cfg->fc_priority = rt->rt_metric - 1; |
| |
| if (rt->rt_flags & RTF_REJECT) { |
| cfg->fc_scope = RT_SCOPE_HOST; |
| cfg->fc_type = RTN_UNREACHABLE; |
| return 0; |
| } |
| |
| cfg->fc_scope = RT_SCOPE_NOWHERE; |
| cfg->fc_type = RTN_UNICAST; |
| |
| if (rt->rt_dev) { |
| char *colon; |
| struct net_device *dev; |
| char devname[IFNAMSIZ]; |
| |
| if (copy_from_user(devname, rt->rt_dev, IFNAMSIZ-1)) |
| return -EFAULT; |
| |
| devname[IFNAMSIZ-1] = 0; |
| colon = strchr(devname, ':'); |
| if (colon) |
| *colon = 0; |
| dev = __dev_get_by_name(net, devname); |
| if (!dev) |
| return -ENODEV; |
| cfg->fc_oif = dev->ifindex; |
| cfg->fc_table = l3mdev_fib_table(dev); |
| if (colon) { |
| struct in_ifaddr *ifa; |
| struct in_device *in_dev = __in_dev_get_rtnl(dev); |
| if (!in_dev) |
| return -ENODEV; |
| *colon = ':'; |
| for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) |
| if (strcmp(ifa->ifa_label, devname) == 0) |
| break; |
| if (!ifa) |
| return -ENODEV; |
| cfg->fc_prefsrc = ifa->ifa_local; |
| } |
| } |
| |
| addr = sk_extract_addr(&rt->rt_gateway); |
| if (rt->rt_gateway.sa_family == AF_INET && addr) { |
| unsigned int addr_type; |
| |
| cfg->fc_gw = addr; |
| addr_type = inet_addr_type_table(net, addr, cfg->fc_table); |
| if (rt->rt_flags & RTF_GATEWAY && |
| addr_type == RTN_UNICAST) |
| cfg->fc_scope = RT_SCOPE_UNIVERSE; |
| } |
| |
| if (cmd == SIOCDELRT) |
| return 0; |
| |
| if (rt->rt_flags & RTF_GATEWAY && !cfg->fc_gw) |
| return -EINVAL; |
| |
| if (cfg->fc_scope == RT_SCOPE_NOWHERE) |
| cfg->fc_scope = RT_SCOPE_LINK; |
| |
| if (rt->rt_flags & (RTF_MTU | RTF_WINDOW | RTF_IRTT)) { |
| struct nlattr *mx; |
| int len = 0; |
| |
| mx = kzalloc(3 * nla_total_size(4), GFP_KERNEL); |
| if (!mx) |
| return -ENOMEM; |
| |
| if (rt->rt_flags & RTF_MTU) |
| len = put_rtax(mx, len, RTAX_ADVMSS, rt->rt_mtu - 40); |
| |
| if (rt->rt_flags & RTF_WINDOW) |
| len = put_rtax(mx, len, RTAX_WINDOW, rt->rt_window); |
| |
| if (rt->rt_flags & RTF_IRTT) |
| len = put_rtax(mx, len, RTAX_RTT, rt->rt_irtt << 3); |
| |
| cfg->fc_mx = mx; |
| cfg->fc_mx_len = len; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * Handle IP routing ioctl calls. |
| * These are used to manipulate the routing tables |
| */ |
| int ip_rt_ioctl(struct net *net, unsigned int cmd, void __user *arg) |
| { |
| struct fib_config cfg; |
| struct rtentry rt; |
| int err; |
| |
| switch (cmd) { |
| case SIOCADDRT: /* Add a route */ |
| case SIOCDELRT: /* Delete a route */ |
| if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) |
| return -EPERM; |
| |
| if (copy_from_user(&rt, arg, sizeof(rt))) |
| return -EFAULT; |
| |
| rtnl_lock(); |
| err = rtentry_to_fib_config(net, cmd, &rt, &cfg); |
| if (err == 0) { |
| struct fib_table *tb; |
| |
| if (cmd == SIOCDELRT) { |
| tb = fib_get_table(net, cfg.fc_table); |
| if (tb) |
| err = fib_table_delete(net, tb, &cfg); |
| else |
| err = -ESRCH; |
| } else { |
| tb = fib_new_table(net, cfg.fc_table); |
| if (tb) |
| err = fib_table_insert(net, tb, &cfg); |
| else |
| err = -ENOBUFS; |
| } |
| |
| /* allocated by rtentry_to_fib_config() */ |
| kfree(cfg.fc_mx); |
| } |
| rtnl_unlock(); |
| return err; |
| } |
| return -EINVAL; |
| } |
| |
| const struct nla_policy rtm_ipv4_policy[RTA_MAX + 1] = { |
| [RTA_DST] = { .type = NLA_U32 }, |
| [RTA_SRC] = { .type = NLA_U32 }, |
| [RTA_IIF] = { .type = NLA_U32 }, |
| [RTA_OIF] = { .type = NLA_U32 }, |
| [RTA_GATEWAY] = { .type = NLA_U32 }, |
| [RTA_PRIORITY] = { .type = NLA_U32 }, |
| [RTA_PREFSRC] = { .type = NLA_U32 }, |
| [RTA_METRICS] = { .type = NLA_NESTED }, |
| [RTA_MULTIPATH] = { .len = sizeof(struct rtnexthop) }, |
| [RTA_FLOW] = { .type = NLA_U32 }, |
| [RTA_ENCAP_TYPE] = { .type = NLA_U16 }, |
| [RTA_ENCAP] = { .type = NLA_NESTED }, |
| [RTA_UID] = { .type = NLA_U32 }, |
| }; |
| |
| static int rtm_to_fib_config(struct net *net, struct sk_buff *skb, |
| struct nlmsghdr *nlh, struct fib_config *cfg) |
| { |
| struct nlattr *attr; |
| int err, remaining; |
| struct rtmsg *rtm; |
| |
| err = nlmsg_validate(nlh, sizeof(*rtm), RTA_MAX, rtm_ipv4_policy); |
| if (err < 0) |
| goto errout; |
| |
| memset(cfg, 0, sizeof(*cfg)); |
| |
| rtm = nlmsg_data(nlh); |
| cfg->fc_dst_len = rtm->rtm_dst_len; |
| cfg->fc_tos = rtm->rtm_tos; |
| cfg->fc_table = rtm->rtm_table; |
| cfg->fc_protocol = rtm->rtm_protocol; |
| cfg->fc_scope = rtm->rtm_scope; |
| cfg->fc_type = rtm->rtm_type; |
| cfg->fc_flags = rtm->rtm_flags; |
| cfg->fc_nlflags = nlh->nlmsg_flags; |
| |
| cfg->fc_nlinfo.portid = NETLINK_CB(skb).portid; |
| cfg->fc_nlinfo.nlh = nlh; |
| cfg->fc_nlinfo.nl_net = net; |
| |
| if (cfg->fc_type > RTN_MAX) { |
| err = -EINVAL; |
| goto errout; |
| } |
| |
| nlmsg_for_each_attr(attr, nlh, sizeof(struct rtmsg), remaining) { |
| switch (nla_type(attr)) { |
| case RTA_DST: |
| cfg->fc_dst = nla_get_be32(attr); |
| break; |
| case RTA_OIF: |
| cfg->fc_oif = nla_get_u32(attr); |
| break; |
| case RTA_GATEWAY: |
| cfg->fc_gw = nla_get_be32(attr); |
| break; |
| case RTA_PRIORITY: |
| cfg->fc_priority = nla_get_u32(attr); |
| break; |
| case RTA_PREFSRC: |
| cfg->fc_prefsrc = nla_get_be32(attr); |
| break; |
| case RTA_METRICS: |
| cfg->fc_mx = nla_data(attr); |
| cfg->fc_mx_len = nla_len(attr); |
| break; |
| case RTA_MULTIPATH: |
| err = lwtunnel_valid_encap_type_attr(nla_data(attr), |
| nla_len(attr)); |
| if (err < 0) |
| goto errout; |
| cfg->fc_mp = nla_data(attr); |
| cfg->fc_mp_len = nla_len(attr); |
| break; |
| case RTA_FLOW: |
| cfg->fc_flow = nla_get_u32(attr); |
| break; |
| case RTA_TABLE: |
| cfg->fc_table = nla_get_u32(attr); |
| break; |
| case RTA_ENCAP: |
| cfg->fc_encap = attr; |
| break; |
| case RTA_ENCAP_TYPE: |
| cfg->fc_encap_type = nla_get_u16(attr); |
| err = lwtunnel_valid_encap_type(cfg->fc_encap_type); |
| if (err < 0) |
| goto errout; |
| break; |
| } |
| } |
| |
| return 0; |
| errout: |
| return err; |
| } |
| |
| static int inet_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh) |
| { |
| struct net *net = sock_net(skb->sk); |
| struct fib_config cfg; |
| struct fib_table *tb; |
| int err; |
| |
| err = rtm_to_fib_config(net, skb, nlh, &cfg); |
| if (err < 0) |
| goto errout; |
| |
| tb = fib_get_table(net, cfg.fc_table); |
| if (!tb) { |
| err = -ESRCH; |
| goto errout; |
| } |
| |
| err = fib_table_delete(net, tb, &cfg); |
| errout: |
| return err; |
| } |
| |
| static int inet_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh) |
| { |
| struct net *net = sock_net(skb->sk); |
| struct fib_config cfg; |
| struct fib_table *tb; |
| int err; |
| |
| err = rtm_to_fib_config(net, skb, nlh, &cfg); |
| if (err < 0) |
| goto errout; |
| |
| tb = fib_new_table(net, cfg.fc_table); |
| if (!tb) { |
| err = -ENOBUFS; |
| goto errout; |
| } |
| |
| err = fib_table_insert(net, tb, &cfg); |
| errout: |
| return err; |
| } |
| |
| static int inet_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) |
| { |
| struct net *net = sock_net(skb->sk); |
| unsigned int h, s_h; |
| unsigned int e = 0, s_e; |
| struct fib_table *tb; |
| struct hlist_head *head; |
| int dumped = 0; |
| |
| if (nlmsg_len(cb->nlh) >= sizeof(struct rtmsg) && |
| ((struct rtmsg *) nlmsg_data(cb->nlh))->rtm_flags & RTM_F_CLONED) |
| return skb->len; |
| |
| s_h = cb->args[0]; |
| s_e = cb->args[1]; |
| |
| rcu_read_lock(); |
| |
| for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) { |
| e = 0; |
| head = &net->ipv4.fib_table_hash[h]; |
| hlist_for_each_entry_rcu(tb, head, tb_hlist) { |
| if (e < s_e) |
| goto next; |
| if (dumped) |
| memset(&cb->args[2], 0, sizeof(cb->args) - |
| 2 * sizeof(cb->args[0])); |
| if (fib_table_dump(tb, skb, cb) < 0) |
| goto out; |
| dumped = 1; |
| next: |
| e++; |
| } |
| } |
| out: |
| rcu_read_unlock(); |
| |
| cb->args[1] = e; |
| cb->args[0] = h; |
| |
| return skb->len; |
| } |
| |
| /* Prepare and feed intra-kernel routing request. |
| * Really, it should be netlink message, but :-( netlink |
| * can be not configured, so that we feed it directly |
| * to fib engine. It is legal, because all events occur |
| * only when netlink is already locked. |
| */ |
| static void fib_magic(int cmd, int type, __be32 dst, int dst_len, struct in_ifaddr *ifa) |
| { |
| struct net *net = dev_net(ifa->ifa_dev->dev); |
| u32 tb_id = l3mdev_fib_table(ifa->ifa_dev->dev); |
| struct fib_table *tb; |
| struct fib_config cfg = { |
| .fc_protocol = RTPROT_KERNEL, |
| .fc_type = type, |
| .fc_dst = dst, |
| .fc_dst_len = dst_len, |
| .fc_prefsrc = ifa->ifa_local, |
| .fc_oif = ifa->ifa_dev->dev->ifindex, |
| .fc_nlflags = NLM_F_CREATE | NLM_F_APPEND, |
| .fc_nlinfo = { |
| .nl_net = net, |
| }, |
| }; |
| |
| if (!tb_id) |
| tb_id = (type == RTN_UNICAST) ? RT_TABLE_MAIN : RT_TABLE_LOCAL; |
| |
| tb = fib_new_table(net, tb_id); |
| if (!tb) |
| return; |
| |
| cfg.fc_table = tb->tb_id; |
| |
| if (type != RTN_LOCAL) |
| cfg.fc_scope = RT_SCOPE_LINK; |
| else |
| cfg.fc_scope = RT_SCOPE_HOST; |
| |
| if (cmd == RTM_NEWROUTE) |
| fib_table_insert(net, tb, &cfg); |
| else |
| fib_table_delete(net, tb, &cfg); |
| } |
| |
| void fib_add_ifaddr(struct in_ifaddr *ifa) |
| { |
| struct in_device *in_dev = ifa->ifa_dev; |
| struct net_device *dev = in_dev->dev; |
| struct in_ifaddr *prim = ifa; |
| __be32 mask = ifa->ifa_mask; |
| __be32 addr = ifa->ifa_local; |
| __be32 prefix = ifa->ifa_address & mask; |
| |
| if (ifa->ifa_flags & IFA_F_SECONDARY) { |
| prim = inet_ifa_byprefix(in_dev, prefix, mask); |
| if (!prim) { |
| pr_warn("%s: bug: prim == NULL\n", __func__); |
| return; |
| } |
| } |
| |
| fib_magic(RTM_NEWROUTE, RTN_LOCAL, addr, 32, prim); |
| |
| if (!(dev->flags & IFF_UP)) |
| return; |
| |
| /* Add broadcast address, if it is explicitly assigned. */ |
| if (ifa->ifa_broadcast && ifa->ifa_broadcast != htonl(0xFFFFFFFF)) |
| fib_magic(RTM_NEWROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim); |
| |
| if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) && |
| (prefix != addr || ifa->ifa_prefixlen < 32)) { |
| if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) |
| fib_magic(RTM_NEWROUTE, |
| dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, |
| prefix, ifa->ifa_prefixlen, prim); |
| |
| /* Add network specific broadcasts, when it takes a sense */ |
| if (ifa->ifa_prefixlen < 31) { |
| fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix, 32, prim); |
| fib_magic(RTM_NEWROUTE, RTN_BROADCAST, prefix | ~mask, |
| 32, prim); |
| } |
| } |
| } |
| |
| /* Delete primary or secondary address. |
| * Optionally, on secondary address promotion consider the addresses |
| * from subnet iprim as deleted, even if they are in device list. |
| * In this case the secondary ifa can be in device list. |
| */ |
| void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim) |
| { |
| struct in_device *in_dev = ifa->ifa_dev; |
| struct net_device *dev = in_dev->dev; |
| struct in_ifaddr *ifa1; |
| struct in_ifaddr *prim = ifa, *prim1 = NULL; |
| __be32 brd = ifa->ifa_address | ~ifa->ifa_mask; |
| __be32 any = ifa->ifa_address & ifa->ifa_mask; |
| #define LOCAL_OK 1 |
| #define BRD_OK 2 |
| #define BRD0_OK 4 |
| #define BRD1_OK 8 |
| unsigned int ok = 0; |
| int subnet = 0; /* Primary network */ |
| int gone = 1; /* Address is missing */ |
| int same_prefsrc = 0; /* Another primary with same IP */ |
| |
| if (ifa->ifa_flags & IFA_F_SECONDARY) { |
| prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask); |
| if (!prim) { |
| /* if the device has been deleted, we don't perform |
| * address promotion |
| */ |
| if (!in_dev->dead) |
| pr_warn("%s: bug: prim == NULL\n", __func__); |
| return; |
| } |
| if (iprim && iprim != prim) { |
| pr_warn("%s: bug: iprim != prim\n", __func__); |
| return; |
| } |
| } else if (!ipv4_is_zeronet(any) && |
| (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) { |
| if (!(ifa->ifa_flags & IFA_F_NOPREFIXROUTE)) |
| fib_magic(RTM_DELROUTE, |
| dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST, |
| any, ifa->ifa_prefixlen, prim); |
| subnet = 1; |
| } |
| |
| if (in_dev->dead) |
| goto no_promotions; |
| |
| /* Deletion is more complicated than add. |
| * We should take care of not to delete too much :-) |
| * |
| * Scan address list to be sure that addresses are really gone. |
| */ |
| |
| for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) { |
| if (ifa1 == ifa) { |
| /* promotion, keep the IP */ |
| gone = 0; |
| continue; |
| } |
| /* Ignore IFAs from our subnet */ |
| if (iprim && ifa1->ifa_mask == iprim->ifa_mask && |
| inet_ifa_match(ifa1->ifa_address, iprim)) |
| continue; |
| |
| /* Ignore ifa1 if it uses different primary IP (prefsrc) */ |
| if (ifa1->ifa_flags & IFA_F_SECONDARY) { |
| /* Another address from our subnet? */ |
| if (ifa1->ifa_mask == prim->ifa_mask && |
| inet_ifa_match(ifa1->ifa_address, prim)) |
| prim1 = prim; |
| else { |
| /* We reached the secondaries, so |
| * same_prefsrc should be determined. |
| */ |
| if (!same_prefsrc) |
| continue; |
| /* Search new prim1 if ifa1 is not |
| * using the current prim1 |
| */ |
| if (!prim1 || |
| ifa1->ifa_mask != prim1->ifa_mask || |
| !inet_ifa_match(ifa1->ifa_address, prim1)) |
| prim1 = inet_ifa_byprefix(in_dev, |
| ifa1->ifa_address, |
| ifa1->ifa_mask); |
| if (!prim1) |
| continue; |
| if (prim1->ifa_local != prim->ifa_local) |
| continue; |
| } |
| } else { |
| if (prim->ifa_local != ifa1->ifa_local) |
| continue; |
| prim1 = ifa1; |
| if (prim != prim1) |
| same_prefsrc = 1; |
| } |
| if (ifa->ifa_local == ifa1->ifa_local) |
| ok |= LOCAL_OK; |
| if (ifa->ifa_broadcast == ifa1->ifa_broadcast) |
| ok |= BRD_OK; |
| if (brd == ifa1->ifa_broadcast) |
| ok |= BRD1_OK; |
| if (any == ifa1->ifa_broadcast) |
| ok |= BRD0_OK; |
| /* primary has network specific broadcasts */ |
| if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) { |
| __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask; |
| __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask; |
| |
| if (!ipv4_is_zeronet(any1)) { |
| if (ifa->ifa_broadcast == brd1 || |
| ifa->ifa_broadcast == any1) |
| ok |= BRD_OK; |
| if (brd == brd1 || brd == any1) |
| ok |= BRD1_OK; |
| if (any == brd1 || any == any1) |
| ok |= BRD0_OK; |
| } |
| } |
| } |
| |
| no_promotions: |
| if (!(ok & BRD_OK)) |
| fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim); |
| if (subnet && ifa->ifa_prefixlen < 31) { |
| if (!(ok & BRD1_OK)) |
| fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim); |
| if (!(ok & BRD0_OK)) |
| fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim); |
| } |
| if (!(ok & LOCAL_OK)) { |
| unsigned int addr_type; |
| |
| fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim); |
| |
| /* Check, that this local address finally disappeared. */ |
| addr_type = inet_addr_type_dev_table(dev_net(dev), dev, |
| ifa->ifa_local); |
| if (gone && addr_type != RTN_LOCAL) { |
| /* And the last, but not the least thing. |
| * We must flush stray FIB entries. |
| * |
| * First of all, we scan fib_info list searching |
| * for stray nexthop entries, then ignite fib_flush. |
| */ |
| if (fib_sync_down_addr(dev, ifa->ifa_local)) |
| fib_flush(dev_net(dev)); |
| } |
| } |
| #undef LOCAL_OK |
| #undef BRD_OK |
| #undef BRD0_OK |
| #undef BRD1_OK |
| } |
| |
| static void nl_fib_lookup(struct net *net, struct fib_result_nl *frn) |
| { |
| |
| struct fib_result res; |
| struct flowi4 fl4 = { |
| .flowi4_mark = frn->fl_mark, |
| .daddr = frn->fl_addr, |
| .flowi4_tos = frn->fl_tos, |
| .flowi4_scope = frn->fl_scope, |
| }; |
| struct fib_table *tb; |
| |
| rcu_read_lock(); |
| |
| tb = fib_get_table(net, frn->tb_id_in); |
| |
| frn->err = -ENOENT; |
| if (tb) { |
| local_bh_disable(); |
| |
| frn->tb_id = tb->tb_id; |
| frn->err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF); |
| |
| if (!frn->err) { |
| frn->prefixlen = res.prefixlen; |
| frn->nh_sel = res.nh_sel; |
| frn->type = res.type; |
| frn->scope = res.scope; |
| } |
| local_bh_enable(); |
| } |
| |
| rcu_read_unlock(); |
| } |
| |
| static void nl_fib_input(struct sk_buff *skb) |
| { |
| struct net *net; |
| struct fib_result_nl *frn; |
| struct nlmsghdr *nlh; |
| u32 portid; |
| |
| net = sock_net(skb->sk); |
| nlh = nlmsg_hdr(skb); |
| if (skb->len < nlmsg_total_size(sizeof(*frn)) || |
| skb->len < nlh->nlmsg_len || |
| nlmsg_len(nlh) < sizeof(*frn)) |
| return; |
| |
| skb = netlink_skb_clone(skb, GFP_KERNEL); |
| if (!skb) |
| return; |
| nlh = nlmsg_hdr(skb); |
| |
| frn = (struct fib_result_nl *) nlmsg_data(nlh); |
| nl_fib_lookup(net, frn); |
| |
| portid = NETLINK_CB(skb).portid; /* netlink portid */ |
| NETLINK_CB(skb).portid = 0; /* from kernel */ |
| NETLINK_CB(skb).dst_group = 0; /* unicast */ |
| netlink_unicast(net->ipv4.fibnl, skb, portid, MSG_DONTWAIT); |
| } |
| |
| static int __net_init nl_fib_lookup_init(struct net *net) |
| { |
| struct sock *sk; |
| struct netlink_kernel_cfg cfg = { |
| .input = nl_fib_input, |
| }; |
| |
| sk = netlink_kernel_create(net, NETLINK_FIB_LOOKUP, &cfg); |
| if (!sk) |
| return -EAFNOSUPPORT; |
| net->ipv4.fibnl = sk; |
| return 0; |
| } |
| |
| static void nl_fib_lookup_exit(struct net *net) |
| { |
| netlink_kernel_release(net->ipv4.fibnl); |
| net->ipv4.fibnl = NULL; |
| } |
| |
| static void fib_disable_ip(struct net_device *dev, unsigned long event, |
| bool force) |
| { |
| if (fib_sync_down_dev(dev, event, force)) |
| fib_flush(dev_net(dev)); |
| rt_cache_flush(dev_net(dev)); |
| arp_ifdown(dev); |
| } |
| |
| static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr) |
| { |
| struct in_ifaddr *ifa = (struct in_ifaddr *)ptr; |
| struct net_device *dev = ifa->ifa_dev->dev; |
| struct net *net = dev_net(dev); |
| |
| switch (event) { |
| case NETDEV_UP: |
| fib_add_ifaddr(ifa); |
| #ifdef CONFIG_IP_ROUTE_MULTIPATH |
| fib_sync_up(dev, RTNH_F_DEAD); |
| #endif |
| atomic_inc(&net->ipv4.dev_addr_genid); |
| rt_cache_flush(dev_net(dev)); |
| break; |
| case NETDEV_DOWN: |
| fib_del_ifaddr(ifa, NULL); |
| atomic_inc(&net->ipv4.dev_addr_genid); |
| if (!ifa->ifa_dev->ifa_list) { |
| /* Last address was deleted from this interface. |
| * Disable IP. |
| */ |
| fib_disable_ip(dev, event, true); |
| } else { |
| rt_cache_flush(dev_net(dev)); |
| } |
| break; |
| } |
| return NOTIFY_DONE; |
| } |
| |
| static int fib_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) |
| { |
| struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
| struct netdev_notifier_changeupper_info *info; |
| struct in_device *in_dev; |
| struct net *net = dev_net(dev); |
| unsigned int flags; |
| |
| if (event == NETDEV_UNREGISTER) { |
| fib_disable_ip(dev, event, true); |
| rt_flush_dev(dev); |
| return NOTIFY_DONE; |
| } |
| |
| in_dev = __in_dev_get_rtnl(dev); |
| if (!in_dev) |
| return NOTIFY_DONE; |
| |
| switch (event) { |
| case NETDEV_UP: |
| for_ifa(in_dev) { |
| fib_add_ifaddr(ifa); |
| } endfor_ifa(in_dev); |
| #ifdef CONFIG_IP_ROUTE_MULTIPATH |
| fib_sync_up(dev, RTNH_F_DEAD); |
| #endif |
| atomic_inc(&net->ipv4.dev_addr_genid); |
| rt_cache_flush(net); |
| break; |
| case NETDEV_DOWN: |
| fib_disable_ip(dev, event, false); |
| break; |
| case NETDEV_CHANGE: |
| flags = dev_get_flags(dev); |
| if (flags & (IFF_RUNNING | IFF_LOWER_UP)) |
| fib_sync_up(dev, RTNH_F_LINKDOWN); |
| else |
| fib_sync_down_dev(dev, event, false); |
| /* fall through */ |
| case NETDEV_CHANGEMTU: |
| rt_cache_flush(net); |
| break; |
| case NETDEV_CHANGEUPPER: |
| info = ptr; |
| /* flush all routes if dev is linked to or unlinked from |
| * an L3 master device (e.g., VRF) |
| */ |
| if (info->upper_dev && netif_is_l3_master(info->upper_dev)) |
| fib_disable_ip(dev, NETDEV_DOWN, true); |
| break; |
| } |
| return NOTIFY_DONE; |
| } |
| |
| static struct notifier_block fib_inetaddr_notifier = { |
| .notifier_call = fib_inetaddr_event, |
| }; |
| |
| static struct notifier_block fib_netdev_notifier = { |
| .notifier_call = fib_netdev_event, |
| }; |
| |
| static int __net_init ip_fib_net_init(struct net *net) |
| { |
| int err; |
| size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ; |
| |
| /* Avoid false sharing : Use at least a full cache line */ |
| size = max_t(size_t, size, L1_CACHE_BYTES); |
| |
| net->ipv4.fib_table_hash = kzalloc(size, GFP_KERNEL); |
| if (!net->ipv4.fib_table_hash) |
| return -ENOMEM; |
| |
| err = fib4_rules_init(net); |
| if (err < 0) |
| goto fail; |
| return 0; |
| |
| fail: |
| kfree(net->ipv4.fib_table_hash); |
| return err; |
| } |
| |
| static void ip_fib_net_exit(struct net *net) |
| { |
| unsigned int i; |
| |
| rtnl_lock(); |
| #ifdef CONFIG_IP_MULTIPLE_TABLES |
| RCU_INIT_POINTER(net->ipv4.fib_main, NULL); |
| RCU_INIT_POINTER(net->ipv4.fib_default, NULL); |
| #endif |
| for (i = 0; i < FIB_TABLE_HASHSZ; i++) { |
| struct hlist_head *head = &net->ipv4.fib_table_hash[i]; |
| struct hlist_node *tmp; |
| struct fib_table *tb; |
| |
| hlist_for_each_entry_safe(tb, tmp, head, tb_hlist) { |
| hlist_del(&tb->tb_hlist); |
| fib_table_flush(net, tb); |
| fib_free_table(tb); |
| } |
| } |
| |
| #ifdef CONFIG_IP_MULTIPLE_TABLES |
| fib4_rules_exit(net); |
| #endif |
| rtnl_unlock(); |
| kfree(net->ipv4.fib_table_hash); |
| } |
| |
| static int __net_init fib_net_init(struct net *net) |
| { |
| int error; |
| |
| #ifdef CONFIG_IP_ROUTE_CLASSID |
| net->ipv4.fib_num_tclassid_users = 0; |
| #endif |
| error = ip_fib_net_init(net); |
| if (error < 0) |
| goto out; |
| error = nl_fib_lookup_init(net); |
| if (error < 0) |
| goto out_nlfl; |
| error = fib_proc_init(net); |
| if (error < 0) |
| goto out_proc; |
| out: |
| return error; |
| |
| out_proc: |
| nl_fib_lookup_exit(net); |
| out_nlfl: |
| ip_fib_net_exit(net); |
| goto out; |
| } |
| |
| static void __net_exit fib_net_exit(struct net *net) |
| { |
| fib_proc_exit(net); |
| nl_fib_lookup_exit(net); |
| ip_fib_net_exit(net); |
| } |
| |
| static struct pernet_operations fib_net_ops = { |
| .init = fib_net_init, |
| .exit = fib_net_exit, |
| }; |
| |
| void __init ip_fib_init(void) |
| { |
| rtnl_register(PF_INET, RTM_NEWROUTE, inet_rtm_newroute, NULL, NULL); |
| rtnl_register(PF_INET, RTM_DELROUTE, inet_rtm_delroute, NULL, NULL); |
| rtnl_register(PF_INET, RTM_GETROUTE, NULL, inet_dump_fib, NULL); |
| |
| register_pernet_subsys(&fib_net_ops); |
| register_netdevice_notifier(&fib_netdev_notifier); |
| register_inetaddr_notifier(&fib_inetaddr_notifier); |
| |
| fib_trie_init(); |
| } |