--- /dev/null
+/* Copyright (c) 2014 Mahesh Bandewar <maheshb@google.com>
+ *
+ * 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 "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));
+}
+
+static void ipvlan_count_rx(const struct ipvl_dev *ipvlan,
+ unsigned int len, bool success, bool mcast)
+{
+ if (!ipvlan)
+ return;
+
+ 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);
+ }
+}
+
+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;
+}
+
+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;
+}
+
+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 (is_v6 && addr->atype == IPVL_IPV6 &&
+ ipv6_addr_equal(&addr->ip6addr, iaddr))
+ return addr;
+ else if (!is_v6 && addr->atype == IPVL_IPV4 &&
+ addr->ip4addr.s_addr ==
+ ((struct in_addr *)iaddr)->s_addr)
+ 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, bool sync)
+{
+ hlist_del_init_rcu(&addr->hlnode);
+ if (sync)
+ synchronize_rcu();
+}
+
+struct ipvl_addr *ipvlan_find_addr(const struct ipvl_dev *ipvlan,
+ const void *iaddr, bool is_v6)
+{
+ struct ipvl_addr *addr;
+
+ list_for_each_entry(addr, &ipvlan->addrs, anode) {
+ if ((is_v6 && addr->atype == IPVL_IPV6 &&
+ ipv6_addr_equal(&addr->ip6addr, iaddr)) ||
+ (!is_v6 && addr->atype == IPVL_IPV4 &&
+ addr->ip4addr.s_addr == ((struct in_addr *)iaddr)->s_addr))
+ return addr;
+ }
+ return NULL;
+}
+
+bool ipvlan_addr_busy(struct ipvl_port *port, void *iaddr, bool is_v6)
+{
+ struct ipvl_dev *ipvlan;
+
+ ASSERT_RTNL();
+
+ list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
+ if (ipvlan_find_addr(ipvlan, iaddr, is_v6))
+ return true;
+ }
+ return false;
+}
+
+static void *ipvlan_get_L3_hdr(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, sizeof(*arph))))
+ 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;
+ }
+ 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) {
+ *type = IPVL_ICMPV6;
+ lyr3h = ip6h + 1;
+ }
+ break;
+ }
+ 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;
+}
+
+static void ipvlan_multicast_frame(struct ipvl_port *port, struct sk_buff *skb,
+ const struct ipvl_dev *in_dev, bool local)
+{
+ struct ethhdr *eth = eth_hdr(skb);
+ struct ipvl_dev *ipvlan;
+ struct sk_buff *nskb;
+ unsigned int len;
+ unsigned int mac_hash;
+ int ret;
+
+ if (skb->protocol == htons(ETH_P_PAUSE))
+ return;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(ipvlan, &port->ipvlans, pnode) {
+ if (local && (ipvlan == in_dev))
+ continue;
+
+ mac_hash = ipvlan_mac_hash(eth->h_dest);
+ if (!test_bit(mac_hash, ipvlan->mac_filters))
+ continue;
+
+ ret = NET_RX_DROP;
+ len = skb->len + ETH_HLEN;
+ nskb = skb_clone(skb, GFP_ATOMIC);
+ if (!nskb)
+ goto mcast_acct;
+
+ if (ether_addr_equal(eth->h_dest, ipvlan->phy_dev->broadcast))
+ nskb->pkt_type = PACKET_BROADCAST;
+ else
+ nskb->pkt_type = PACKET_MULTICAST;
+
+ nskb->dev = ipvlan->dev;
+ if (local)
+ ret = dev_forward_skb(ipvlan->dev, nskb);
+ else
+ ret = netif_rx(nskb);
+mcast_acct:
+ ipvlan_count_rx(ipvlan, len, ret == NET_RX_SUCCESS, true);
+ }
+ rcu_read_unlock();
+
+ /* Locally generated? ...Forward a copy to the main-device as
+ * well. On the RX side we'll ignore it (wont give it to any
+ * of the virtual devices.
+ */
+ if (local) {
+ nskb = skb_clone(skb, GFP_ATOMIC);
+ if (nskb) {
+ if (ether_addr_equal(eth->h_dest, port->dev->broadcast))
+ nskb->pkt_type = PACKET_BROADCAST;
+ else
+ nskb->pkt_type = PACKET_MULTICAST;
+
+ dev_forward_skb(port->dev, nskb);
+ }
+ }
+}
+
+static int ipvlan_rcv_frame(struct ipvl_addr *addr, struct sk_buff *skb,
+ 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;
+
+ len = skb->len + ETH_HLEN;
+ if (unlikely(!(dev->flags & IFF_UP))) {
+ kfree_skb(skb);
+ goto out;
+ }
+
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ if (!skb)
+ goto out;
+
+ skb->dev = dev;
+ skb->pkt_type = PACKET_HOST;
+
+ if (local) {
+ if (dev_forward_skb(ipvlan->dev, skb) == NET_RX_SUCCESS)
+ success = true;
+ } else {
+ ret = RX_HANDLER_ANOTHER;
+ success = true;
+ }
+
+out:
+ ipvlan_count_rx(ipvlan, len, success, false);
+ return ret;
+}
+
+static struct ipvl_addr *ipvlan_addr_lookup(struct ipvl_port *port,
+ void *lyr3h, int addr_type,
+ bool use_dest)
+{
+ struct ipvl_addr *addr = NULL;
+
+ if (addr_type == 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);
+ } else if (addr_type == 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);
+ }
+ } else if (addr_type == 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);
+ } else if (addr_type == 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);
+ }
+
+ return addr;
+}
+
+static int ipvlan_process_v4_outbound(struct sk_buff *skb)
+{
+ const struct iphdr *ip4h = ip_hdr(skb);
+ struct net_device *dev = skb->dev;
+ struct rtable *rt;
+ int err, ret = NET_XMIT_DROP;
+ struct flowi4 fl4 = {
+ .flowi4_oif = dev_get_iflink(dev),
+ .flowi4_tos = RT_TOS(ip4h->tos),
+ .flowi4_flags = FLOWI_FLAG_ANYSRC,
+ .daddr = ip4h->daddr,
+ .saddr = ip4h->saddr,
+ };
+
+ rt = ip_route_output_flow(dev_net(dev), &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_drop(skb);
+ skb_dst_set(skb, &rt->dst);
+ err = ip_local_out(skb);
+ if (unlikely(net_xmit_eval(err)))
+ dev->stats.tx_errors++;
+ else
+ ret = NET_XMIT_SUCCESS;
+ goto out;
+err:
+ dev->stats.tx_errors++;
+ kfree_skb(skb);
+out:
+ return ret;
+}
+
+static int ipvlan_process_v6_outbound(struct sk_buff *skb)
+{
+ const struct ipv6hdr *ip6h = ipv6_hdr(skb);
+ struct net_device *dev = skb->dev;
+ struct dst_entry *dst;
+ int err, ret = NET_XMIT_DROP;
+ struct flowi6 fl6 = {
+ .flowi6_iif = skb->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,
+ };
+
+ dst = ip6_route_output(dev_net(dev), NULL, &fl6);
+ if (dst->error) {
+ ret = dst->error;
+ dst_release(dst);
+ goto err;
+ }
+ skb_dst_drop(skb);
+ skb_dst_set(skb, dst);
+ err = ip6_local_out(skb);
+ if (unlikely(net_xmit_eval(err)))
+ dev->stats.tx_errors++;
+ else
+ ret = NET_XMIT_SUCCESS;
+ goto out;
+err:
+ dev->stats.tx_errors++;
+ kfree_skb(skb);
+out:
+ return ret;
+}
+
+static int ipvlan_process_outbound(struct sk_buff *skb,
+ const struct ipvl_dev *ipvlan)
+{
+ struct ethhdr *ethh = eth_hdr(skb);
+ int ret = NET_XMIT_DROP;
+
+ /* In this mode we dont care about multicast and broadcast traffic */
+ if (is_multicast_ether_addr(ethh->h_dest)) {
+ pr_warn_ratelimited("Dropped {multi|broad}cast of type= [%x]\n",
+ ntohs(skb->protocol));
+ kfree_skb(skb);
+ goto out;
+ }
+
+ /* 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)) {
+ 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 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(skb, &addr_type);
+ if (!lyr3h)
+ goto out;
+
+ addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);
+ if (addr)
+ return ipvlan_rcv_frame(addr, skb, true);
+
+out:
+ skb->dev = ipvlan->phy_dev;
+ return ipvlan_process_outbound(skb, ipvlan);
+}
+
+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 = eth_hdr(skb);
+ struct ipvl_addr *addr;
+ void *lyr3h;
+ int addr_type;
+
+ if (ether_addr_equal(eth->h_dest, eth->h_source)) {
+ lyr3h = ipvlan_get_L3_hdr(skb, &addr_type);
+ if (lyr3h) {
+ addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);
+ if (addr)
+ return ipvlan_rcv_frame(addr, skb, true);
+ }
+ 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.
+ */
+ return dev_forward_skb(ipvlan->phy_dev, skb);
+
+ } else if (is_multicast_ether_addr(eth->h_dest)) {
+ u8 ip_summed = skb->ip_summed;
+
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ ipvlan_multicast_frame(ipvlan->port, skb, ipvlan, true);
+ skb->ip_summed = ip_summed;
+ }
+
+ 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(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:
+ 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(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(skb, &addr_type);
+ if (!lyr3h)
+ goto out;
+
+ addr = ipvlan_addr_lookup(port, lyr3h, addr_type, true);
+ if (addr)
+ ret = ipvlan_rcv_frame(addr, skb, 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;
+ void *lyr3h;
+ int addr_type;
+
+ if (is_multicast_ether_addr(eth->h_dest)) {
+ if (ipvlan_external_frame(skb, port))
+ ipvlan_multicast_frame(port, skb, NULL, false);
+ } else {
+ struct ipvl_addr *addr;
+
+ lyr3h = ipvlan_get_L3_hdr(skb, &addr_type);
+ if (!lyr3h)
+ return ret;
+
+ addr = ipvlan_addr_lookup(port, lyr3h, addr_type, true);
+ if (addr)
+ ret = ipvlan_rcv_frame(addr, skb, false);
+ }
+
+ 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);
+ }
+
+ /* Should not reach here */
+ WARN_ONCE(true, "ipvlan_handle_frame() called for mode = [%hx]\n",
+ port->mode);
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
Code Review / kvmfornfv.git / blobdiff