// SPDX-License-Identifier: GPL-2.0-or-later /* Copyright (c) 2014 Mahesh Bandewar */ #include "ipvlan.h" static u32 ipvlan_jhash_secret __read_mostly; void ipvlan_init_secret(void) { net_get_random_once(&ipvlan_jhash_secret, sizeof(ipvlan_jhash_secret)); } void ipvlan_count_rx(const struct ipvl_dev *ipvlan, unsigned int len, bool success, bool mcast) { if (likely(success)) { struct ipvl_pcpu_stats *pcptr; pcptr = this_cpu_ptr(ipvlan->pcpu_stats); u64_stats_update_begin(&pcptr->syncp); pcptr->rx_pkts++; pcptr->rx_bytes += len; if (mcast) pcptr->rx_mcast++; u64_stats_update_end(&pcptr->syncp); } else { this_cpu_inc(ipvlan->pcpu_stats->rx_errs); } } EXPORT_SYMBOL_GPL(ipvlan_count_rx); #if IS_ENABLED(CONFIG_IPV6) static u8 ipvlan_get_v6_hash(const void *iaddr) { const struct in6_addr *ip6_addr = iaddr; return __ipv6_addr_jhash(ip6_addr, ipvlan_jhash_secret) & IPVLAN_HASH_MASK; } #else static u8 ipvlan_get_v6_hash(const void *iaddr) { return 0; } #endif static u8 ipvlan_get_v4_hash(const void *iaddr) { const struct in_addr *ip4_addr = iaddr; return jhash_1word(ip4_addr->s_addr, ipvlan_jhash_secret) & IPVLAN_HASH_MASK; } static bool addr_equal(bool is_v6, struct ipvl_addr *addr, const void *iaddr) { if (!is_v6 && addr->atype == IPVL_IPV4) { struct in_addr *i4addr = (struct in_addr *)iaddr; return addr->ip4addr.s_addr == i4addr->s_addr; #if IS_ENABLED(CONFIG_IPV6) } else if (is_v6 && addr->atype == IPVL_IPV6) { struct in6_addr *i6addr = (struct in6_addr *)iaddr; return ipv6_addr_equal(&addr->ip6addr, i6addr); #endif } return false; } static struct ipvl_addr *ipvlan_ht_addr_lookup(const struct ipvl_port *port, const void *iaddr, bool is_v6) { struct ipvl_addr *addr; u8 hash; hash = is_v6 ? ipvlan_get_v6_hash(iaddr) : ipvlan_get_v4_hash(iaddr); hlist_for_each_entry_rcu(addr, &port->hlhead[hash], hlnode) if (addr_equal(is_v6, addr, iaddr)) return addr; return NULL; } void ipvlan_ht_addr_add(struct ipvl_dev *ipvlan, struct ipvl_addr *addr) { struct ipvl_port *port = ipvlan->port; u8 hash; hash = (addr->atype == IPVL_IPV6) ? ipvlan_get_v6_hash(&addr->ip6addr) : ipvlan_get_v4_hash(&addr->ip4addr); if (hlist_unhashed(&addr->hlnode)) hlist_add_head_rcu(&addr->hlnode, &port->hlhead[hash]); } void ipvlan_ht_addr_del(struct ipvl_addr *addr) { hlist_del_init_rcu(&addr->hlnode); } struct ipvl_addr *ipvlan_find_addr(const struct ipvl_dev *ipvlan, const void *iaddr, bool is_v6) { struct ipvl_addr *addr, *ret = NULL; rcu_read_lock(); list_for_each_entry_rcu(addr, &ipvlan->addrs, anode) { if (addr_equal(is_v6, addr, iaddr)) { ret = addr; break; } } rcu_read_unlock(); return ret; } bool ipvlan_addr_busy(struct ipvl_port *port, void *iaddr, bool is_v6) { struct ipvl_dev *ipvlan; bool ret = false; rcu_read_lock(); list_for_each_entry_rcu(ipvlan, &port->ipvlans, pnode) { if (ipvlan_find_addr(ipvlan, iaddr, is_v6)) { ret = true; break; } } rcu_read_unlock(); return ret; } void *ipvlan_get_L3_hdr(struct ipvl_port *port, struct sk_buff *skb, int *type) { void *lyr3h = NULL; switch (skb->protocol) { case htons(ETH_P_ARP): { struct arphdr *arph; if (unlikely(!pskb_may_pull(skb, arp_hdr_len(port->dev)))) return NULL; arph = arp_hdr(skb); *type = IPVL_ARP; lyr3h = arph; break; } case htons(ETH_P_IP): { u32 pktlen; struct iphdr *ip4h; if (unlikely(!pskb_may_pull(skb, sizeof(*ip4h)))) return NULL; ip4h = ip_hdr(skb); pktlen = ntohs(ip4h->tot_len); if (ip4h->ihl < 5 || ip4h->version != 4) return NULL; if (skb->len < pktlen || pktlen < (ip4h->ihl * 4)) return NULL; *type = IPVL_IPV4; lyr3h = ip4h; break; } #if IS_ENABLED(CONFIG_IPV6) case htons(ETH_P_IPV6): { struct ipv6hdr *ip6h; if (unlikely(!pskb_may_pull(skb, sizeof(*ip6h)))) return NULL; ip6h = ipv6_hdr(skb); if (ip6h->version != 6) return NULL; *type = IPVL_IPV6; lyr3h = ip6h; /* Only Neighbour Solicitation pkts need different treatment */ if (ipv6_addr_any(&ip6h->saddr) && ip6h->nexthdr == NEXTHDR_ICMP) { struct icmp6hdr *icmph; if (unlikely(!pskb_may_pull(skb, sizeof(*ip6h) + sizeof(*icmph)))) return NULL; ip6h = ipv6_hdr(skb); icmph = (struct icmp6hdr *)(ip6h + 1); if (icmph->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION) { /* Need to access the ipv6 address in body */ if (unlikely(!pskb_may_pull(skb, sizeof(*ip6h) + sizeof(*icmph) + sizeof(struct in6_addr)))) return NULL; ip6h = ipv6_hdr(skb); icmph = (struct icmp6hdr *)(ip6h + 1); } *type = IPVL_ICMPV6; lyr3h = icmph; } break; } #endif default: return NULL; } return lyr3h; } unsigned int ipvlan_mac_hash(const unsigned char *addr) { u32 hash = jhash_1word(__get_unaligned_cpu32(addr+2), ipvlan_jhash_secret); return hash & IPVLAN_MAC_FILTER_MASK; } void ipvlan_process_multicast(struct work_struct *work) { struct ipvl_port *port = container_of(work, struct ipvl_port, wq); struct ethhdr *ethh; struct ipvl_dev *ipvlan; struct sk_buff *skb, *nskb; struct sk_buff_head list; unsigned int len; unsigned int mac_hash; int ret; u8 pkt_type; bool tx_pkt; __skb_queue_head_init(&list); spin_lock_bh(&port->backlog.lock); skb_queue_splice_tail_init(&port->backlog, &list); spin_unlock_bh(&port->backlog.lock); while ((skb = __skb_dequeue(&list)) != NULL) { struct net_device *dev = skb->dev; bool consumed = false; ethh = eth_hdr(skb); tx_pkt = IPVL_SKB_CB(skb)->tx_pkt; mac_hash = ipvlan_mac_hash(ethh->h_dest); if (ether_addr_equal(ethh->h_dest, port->dev->broadcast)) pkt_type = PACKET_BROADCAST; else pkt_type = PACKET_MULTICAST; rcu_read_lock(); list_for_each_entry_rcu(ipvlan, &port->ipvlans, pnode) { if (tx_pkt && (ipvlan->dev == skb->dev)) continue; if (!test_bit(mac_hash, ipvlan->mac_filters)) continue; if (!(ipvlan->dev->flags & IFF_UP)) continue; ret = NET_RX_DROP; len = skb->len + ETH_HLEN; nskb = skb_clone(skb, GFP_ATOMIC); local_bh_disable(); if (nskb) { consumed = true; nskb->pkt_type = pkt_type; nskb->dev = ipvlan->dev; if (tx_pkt) ret = dev_forward_skb(ipvlan->dev, nskb); else ret = netif_rx(nskb); } ipvlan_count_rx(ipvlan, len, ret == NET_RX_SUCCESS, true); local_bh_enable(); } rcu_read_unlock(); if (tx_pkt) { /* If the packet originated here, send it out. */ skb->dev = port->dev; skb->pkt_type = pkt_type; dev_queue_xmit(skb); } else { if (consumed) consume_skb(skb); else kfree_skb(skb); } if (dev) dev_put(dev); cond_resched(); } } static void ipvlan_skb_crossing_ns(struct sk_buff *skb, struct net_device *dev) { bool xnet = true; if (dev) xnet = !net_eq(dev_net(skb->dev), dev_net(dev)); skb_scrub_packet(skb, xnet); if (dev) skb->dev = dev; } static int ipvlan_rcv_frame(struct ipvl_addr *addr, struct sk_buff **pskb, bool local) { struct ipvl_dev *ipvlan = addr->master; struct net_device *dev = ipvlan->dev; unsigned int len; rx_handler_result_t ret = RX_HANDLER_CONSUMED; bool success = false; struct sk_buff *skb = *pskb; len = skb->len + ETH_HLEN; /* Only packets exchanged between two local slaves need to have * device-up check as well as skb-share check. */ if (local) { if (unlikely(!(dev->flags & IFF_UP))) { kfree_skb(skb); goto out; } skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) goto out; *pskb = skb; } if (local) { skb->pkt_type = PACKET_HOST; if (dev_forward_skb(ipvlan->dev, skb) == NET_RX_SUCCESS) success = true; } else { skb->dev = dev; ret = RX_HANDLER_ANOTHER; success = true; } out: ipvlan_count_rx(ipvlan, len, success, false); return ret; } struct ipvl_addr *ipvlan_addr_lookup(struct ipvl_port *port, void *lyr3h, int addr_type, bool use_dest) { struct ipvl_addr *addr = NULL; switch (addr_type) { #if IS_ENABLED(CONFIG_IPV6) case IPVL_IPV6: { struct ipv6hdr *ip6h; struct in6_addr *i6addr; ip6h = (struct ipv6hdr *)lyr3h; i6addr = use_dest ? &ip6h->daddr : &ip6h->saddr; addr = ipvlan_ht_addr_lookup(port, i6addr, true); break; } case IPVL_ICMPV6: { struct nd_msg *ndmh; struct in6_addr *i6addr; /* Make sure that the NeighborSolicitation ICMPv6 packets * are handled to avoid DAD issue. */ ndmh = (struct nd_msg *)lyr3h; if (ndmh->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION) { i6addr = &ndmh->target; addr = ipvlan_ht_addr_lookup(port, i6addr, true); } break; } #endif case IPVL_IPV4: { struct iphdr *ip4h; __be32 *i4addr; ip4h = (struct iphdr *)lyr3h; i4addr = use_dest ? &ip4h->daddr : &ip4h->saddr; addr = ipvlan_ht_addr_lookup(port, i4addr, false); break; } case IPVL_ARP: { struct arphdr *arph; unsigned char *arp_ptr; __be32 dip; arph = (struct arphdr *)lyr3h; arp_ptr = (unsigned char *)(arph + 1); if (use_dest) arp_ptr += (2 * port->dev->addr_len) + 4; else arp_ptr += port->dev->addr_len; memcpy(&dip, arp_ptr, 4); addr = ipvlan_ht_addr_lookup(port, &dip, false); break; } } return addr; } static noinline_for_stack int ipvlan_process_v4_outbound(struct sk_buff *skb) { const struct iphdr *ip4h = ip_hdr(skb); struct net_device *dev = skb->dev; struct net *net = dev_net(dev); struct rtable *rt; int err, ret = NET_XMIT_DROP; struct flowi4 fl4 = { .flowi4_oif = dev->ifindex, .flowi4_tos = RT_TOS(ip4h->tos), .flowi4_flags = FLOWI_FLAG_ANYSRC, .flowi4_mark = skb->mark, .daddr = ip4h->daddr, .saddr = ip4h->saddr, }; rt = ip_route_output_flow(net, &fl4, NULL); if (IS_ERR(rt)) goto err; if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) { ip_rt_put(rt); goto err; } skb_dst_set(skb, &rt->dst); memset(IPCB(skb), 0, sizeof(*IPCB(skb))); err = ip_local_out(net, skb->sk, skb); if (unlikely(net_xmit_eval(err))) DEV_STATS_INC(dev, tx_errors); else ret = NET_XMIT_SUCCESS; goto out; err: DEV_STATS_INC(dev, tx_errors); kfree_skb(skb); out: return ret; } #if IS_ENABLED(CONFIG_IPV6) static noinline_for_stack int ipvlan_route_v6_outbound(struct net_device *dev, struct sk_buff *skb) { const struct ipv6hdr *ip6h = ipv6_hdr(skb); struct flowi6 fl6 = { .flowi6_oif = dev->ifindex, .daddr = ip6h->daddr, .saddr = ip6h->saddr, .flowi6_flags = FLOWI_FLAG_ANYSRC, .flowlabel = ip6_flowinfo(ip6h), .flowi6_mark = skb->mark, .flowi6_proto = ip6h->nexthdr, }; struct dst_entry *dst; int err; dst = ip6_route_output(dev_net(dev), NULL, &fl6); err = dst->error; if (err) { dst_release(dst); return err; } skb_dst_set(skb, dst); return 0; } static int ipvlan_process_v6_outbound(struct sk_buff *skb) { struct net_device *dev = skb->dev; int err, ret = NET_XMIT_DROP; err = ipvlan_route_v6_outbound(dev, skb); if (unlikely(err)) { DEV_STATS_INC(dev, tx_errors); kfree_skb(skb); return err; } memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); err = ip6_local_out(dev_net(dev), skb->sk, skb); if (unlikely(net_xmit_eval(err))) DEV_STATS_INC(dev, tx_errors); else ret = NET_XMIT_SUCCESS; return ret; } #else static int ipvlan_process_v6_outbound(struct sk_buff *skb) { return NET_XMIT_DROP; } #endif static int ipvlan_process_outbound(struct sk_buff *skb) { int ret = NET_XMIT_DROP; /* The ipvlan is a pseudo-L2 device, so the packets that we receive * will have L2; which need to discarded and processed further * in the net-ns of the main-device. */ if (skb_mac_header_was_set(skb)) { /* In this mode we dont care about * multicast and broadcast traffic */ struct ethhdr *ethh = eth_hdr(skb); if (is_multicast_ether_addr(ethh->h_dest)) { pr_debug_ratelimited( "Dropped {multi|broad}cast of type=[%x]\n", ntohs(skb->protocol)); kfree_skb(skb); goto out; } skb_pull(skb, sizeof(*ethh)); skb->mac_header = (typeof(skb->mac_header))~0U; skb_reset_network_header(skb); } if (skb->protocol == htons(ETH_P_IPV6)) ret = ipvlan_process_v6_outbound(skb); else if (skb->protocol == htons(ETH_P_IP)) ret = ipvlan_process_v4_outbound(skb); else { pr_warn_ratelimited("Dropped outbound packet type=%x\n", ntohs(skb->protocol)); kfree_skb(skb); } out: return ret; } static void ipvlan_multicast_enqueue(struct ipvl_port *port, struct sk_buff *skb, bool tx_pkt) { if (skb->protocol == htons(ETH_P_PAUSE)) { kfree_skb(skb); return; } /* Record that the deferred packet is from TX or RX path. By * looking at mac-addresses on packet will lead to erronus decisions. * (This would be true for a loopback-mode on master device or a * hair-pin mode of the switch.) */ IPVL_SKB_CB(skb)->tx_pkt = tx_pkt; spin_lock(&port->backlog.lock); if (skb_queue_len(&port->backlog) < IPVLAN_QBACKLOG_LIMIT) { if (skb->dev) dev_hold(skb->dev); __skb_queue_tail(&port->backlog, skb); spin_unlock(&port->backlog.lock); schedule_work(&port->wq); } else { spin_unlock(&port->backlog.lock); atomic_long_inc(&skb->dev->rx_dropped); kfree_skb(skb); } } static int ipvlan_xmit_mode_l3(struct sk_buff *skb, struct net_device *dev) { const struct ipvl_dev *ipvlan = netdev_priv(dev); void *lyr3h; struct ipvl_addr *addr; int addr_type; lyr3h = ipvlan_get_L3_hdr(ipvlan->port, skb, &addr_type); if (!lyr3h) goto out; if (!ipvlan_is_vepa(ipvlan->port)) { addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true); if (addr) { if (ipvlan_is_private(ipvlan->port)) { consume_skb(skb); return NET_XMIT_DROP; } ipvlan_rcv_frame(addr, &skb, true); return NET_XMIT_SUCCESS; } } out: ipvlan_skb_crossing_ns(skb, ipvlan->phy_dev); return ipvlan_process_outbound(skb); } static int ipvlan_xmit_mode_l2(struct sk_buff *skb, struct net_device *dev) { const struct ipvl_dev *ipvlan = netdev_priv(dev); struct ethhdr *eth = skb_eth_hdr(skb); struct ipvl_addr *addr; void *lyr3h; int addr_type; if (!ipvlan_is_vepa(ipvlan->port) && ether_addr_equal(eth->h_dest, eth->h_source)) { lyr3h = ipvlan_get_L3_hdr(ipvlan->port, skb, &addr_type); if (lyr3h) { addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true); if (addr) { if (ipvlan_is_private(ipvlan->port)) { consume_skb(skb); return NET_XMIT_DROP; } ipvlan_rcv_frame(addr, &skb, true); return NET_XMIT_SUCCESS; } } skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) return NET_XMIT_DROP; /* Packet definitely does not belong to any of the * virtual devices, but the dest is local. So forward * the skb for the main-dev. At the RX side we just return * RX_PASS for it to be processed further on the stack. */ dev_forward_skb(ipvlan->phy_dev, skb); return NET_XMIT_SUCCESS; } else if (is_multicast_ether_addr(eth->h_dest)) { skb_reset_mac_header(skb); ipvlan_skb_crossing_ns(skb, NULL); ipvlan_multicast_enqueue(ipvlan->port, skb, true); return NET_XMIT_SUCCESS; } skb->dev = ipvlan->phy_dev; return dev_queue_xmit(skb); } int ipvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev) { struct ipvl_dev *ipvlan = netdev_priv(dev); struct ipvl_port *port = ipvlan_port_get_rcu_bh(ipvlan->phy_dev); if (!port) goto out; if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr)))) goto out; switch(port->mode) { case IPVLAN_MODE_L2: return ipvlan_xmit_mode_l2(skb, dev); case IPVLAN_MODE_L3: #ifdef CONFIG_IPVLAN_L3S case IPVLAN_MODE_L3S: #endif return ipvlan_xmit_mode_l3(skb, dev); } /* Should not reach here */ WARN_ONCE(true, "ipvlan_queue_xmit() called for mode = [%hx]\n", port->mode); out: kfree_skb(skb); return NET_XMIT_DROP; } static bool ipvlan_external_frame(struct sk_buff *skb, struct ipvl_port *port) { struct ethhdr *eth = eth_hdr(skb); struct ipvl_addr *addr; void *lyr3h; int addr_type; if (ether_addr_equal(eth->h_source, skb->dev->dev_addr)) { lyr3h = ipvlan_get_L3_hdr(port, skb, &addr_type); if (!lyr3h) return true; addr = ipvlan_addr_lookup(port, lyr3h, addr_type, false); if (addr) return false; } return true; } static rx_handler_result_t ipvlan_handle_mode_l3(struct sk_buff **pskb, struct ipvl_port *port) { void *lyr3h; int addr_type; struct ipvl_addr *addr; struct sk_buff *skb = *pskb; rx_handler_result_t ret = RX_HANDLER_PASS; lyr3h = ipvlan_get_L3_hdr(port, skb, &addr_type); if (!lyr3h) goto out; addr = ipvlan_addr_lookup(port, lyr3h, addr_type, true); if (addr) ret = ipvlan_rcv_frame(addr, pskb, false); out: return ret; } static rx_handler_result_t ipvlan_handle_mode_l2(struct sk_buff **pskb, struct ipvl_port *port) { struct sk_buff *skb = *pskb; struct ethhdr *eth = eth_hdr(skb); rx_handler_result_t ret = RX_HANDLER_PASS; if (is_multicast_ether_addr(eth->h_dest)) { if (ipvlan_external_frame(skb, port)) { struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC); /* External frames are queued for device local * distribution, but a copy is given to master * straight away to avoid sending duplicates later * when work-queue processes this frame. This is * achieved by returning RX_HANDLER_PASS. */ if (nskb) { ipvlan_skb_crossing_ns(nskb, NULL); ipvlan_multicast_enqueue(port, nskb, false); } } } else { /* Perform like l3 mode for non-multicast packet */ ret = ipvlan_handle_mode_l3(pskb, port); } return ret; } rx_handler_result_t ipvlan_handle_frame(struct sk_buff **pskb) { struct sk_buff *skb = *pskb; struct ipvl_port *port = ipvlan_port_get_rcu(skb->dev); if (!port) return RX_HANDLER_PASS; switch (port->mode) { case IPVLAN_MODE_L2: return ipvlan_handle_mode_l2(pskb, port); case IPVLAN_MODE_L3: return ipvlan_handle_mode_l3(pskb, port); #ifdef CONFIG_IPVLAN_L3S case IPVLAN_MODE_L3S: return RX_HANDLER_PASS; #endif } /* Should not reach here */ WARN_ONCE(true, "ipvlan_handle_frame() called for mode = [%hx]\n", port->mode); kfree_skb(skb); return RX_HANDLER_CONSUMED; }