From 4fbae7d83c98c30efcf0a2a2ac55fbb75ef5a1a5 Mon Sep 17 00:00:00 2001 From: Mahesh Bandewar Date: Fri, 16 Sep 2016 12:59:19 -0700 Subject: ipvlan: Introduce l3s mode In a typical IPvlan L3 setup where master is in default-ns and each slave is into different (slave) ns. In this setup egress packet processing for traffic originating from slave-ns will hit all NF_HOOKs in slave-ns as well as default-ns. However same is not true for ingress processing. All these NF_HOOKs are hit only in the slave-ns skipping them in the default-ns. IPvlan in L3 mode is restrictive and if admins want to deploy iptables rules in default-ns, this asymmetric data path makes it impossible to do so. This patch makes use of the l3_rcv() (added as part of l3mdev enhancements) to perform input route lookup on RX packets without changing the skb->dev and then uses nf_hook at NF_INET_LOCAL_IN to change the skb->dev just before handing over skb to L4. Signed-off-by: Mahesh Bandewar CC: David Ahern Reviewed-by: David Ahern Signed-off-by: David S. Miller --- drivers/net/Kconfig | 1 + drivers/net/ipvlan/ipvlan.h | 6 +++ drivers/net/ipvlan/ipvlan_core.c | 94 ++++++++++++++++++++++++++++++++++++++++ drivers/net/ipvlan/ipvlan_main.c | 87 ++++++++++++++++++++++++++++++++++--- 4 files changed, 181 insertions(+), 7 deletions(-) (limited to 'drivers') diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index 0c5415b..8768a62 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -149,6 +149,7 @@ config IPVLAN tristate "IP-VLAN support" depends on INET depends on IPV6 + depends on NET_L3_MASTER_DEV ---help--- This allows one to create virtual devices off of a main interface and packets will be delivered based on the dest L3 (IPv6/IPv4 addr) diff --git a/drivers/net/ipvlan/ipvlan.h b/drivers/net/ipvlan/ipvlan.h index 695a5dc..7e0732f 100644 --- a/drivers/net/ipvlan/ipvlan.h +++ b/drivers/net/ipvlan/ipvlan.h @@ -23,11 +23,13 @@ #include #include #include +#include #include #include #include #include #include +#include #define IPVLAN_DRV "ipvlan" #define IPV_DRV_VER "0.1" @@ -124,4 +126,8 @@ struct ipvl_addr *ipvlan_find_addr(const struct ipvl_dev *ipvlan, const void *iaddr, bool is_v6); bool ipvlan_addr_busy(struct ipvl_port *port, void *iaddr, bool is_v6); void ipvlan_ht_addr_del(struct ipvl_addr *addr); +struct sk_buff *ipvlan_l3_rcv(struct net_device *dev, struct sk_buff *skb, + u16 proto); +unsigned int ipvlan_nf_input(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state); #endif /* __IPVLAN_H */ diff --git a/drivers/net/ipvlan/ipvlan_core.c b/drivers/net/ipvlan/ipvlan_core.c index b5f9511..b4e9907 100644 --- a/drivers/net/ipvlan/ipvlan_core.c +++ b/drivers/net/ipvlan/ipvlan_core.c @@ -560,6 +560,7 @@ int ipvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev) case IPVLAN_MODE_L2: return ipvlan_xmit_mode_l2(skb, dev); case IPVLAN_MODE_L3: + case IPVLAN_MODE_L3S: return ipvlan_xmit_mode_l3(skb, dev); } @@ -664,6 +665,8 @@ rx_handler_result_t ipvlan_handle_frame(struct sk_buff **pskb) return ipvlan_handle_mode_l2(pskb, port); case IPVLAN_MODE_L3: return ipvlan_handle_mode_l3(pskb, port); + case IPVLAN_MODE_L3S: + return RX_HANDLER_PASS; } /* Should not reach here */ @@ -672,3 +675,94 @@ rx_handler_result_t ipvlan_handle_frame(struct sk_buff **pskb) kfree_skb(skb); return RX_HANDLER_CONSUMED; } + +static struct ipvl_addr *ipvlan_skb_to_addr(struct sk_buff *skb, + struct net_device *dev) +{ + struct ipvl_addr *addr = NULL; + struct ipvl_port *port; + void *lyr3h; + int addr_type; + + if (!dev || !netif_is_ipvlan_port(dev)) + goto out; + + port = ipvlan_port_get_rcu(dev); + if (!port || port->mode != IPVLAN_MODE_L3S) + goto out; + + lyr3h = ipvlan_get_L3_hdr(skb, &addr_type); + if (!lyr3h) + goto out; + + addr = ipvlan_addr_lookup(port, lyr3h, addr_type, true); +out: + return addr; +} + +struct sk_buff *ipvlan_l3_rcv(struct net_device *dev, struct sk_buff *skb, + u16 proto) +{ + struct ipvl_addr *addr; + struct net_device *sdev; + + addr = ipvlan_skb_to_addr(skb, dev); + if (!addr) + goto out; + + sdev = addr->master->dev; + switch (proto) { + case AF_INET: + { + int err; + struct iphdr *ip4h = ip_hdr(skb); + + err = ip_route_input_noref(skb, ip4h->daddr, ip4h->saddr, + ip4h->tos, sdev); + if (unlikely(err)) + goto out; + break; + } + case AF_INET6: + { + struct dst_entry *dst; + struct ipv6hdr *ip6h = ipv6_hdr(skb); + int flags = RT6_LOOKUP_F_HAS_SADDR; + struct flowi6 fl6 = { + .flowi6_iif = sdev->ifindex, + .daddr = ip6h->daddr, + .saddr = ip6h->saddr, + .flowlabel = ip6_flowinfo(ip6h), + .flowi6_mark = skb->mark, + .flowi6_proto = ip6h->nexthdr, + }; + + skb_dst_drop(skb); + dst = ip6_route_input_lookup(dev_net(sdev), sdev, &fl6, flags); + skb_dst_set(skb, dst); + break; + } + default: + break; + } + +out: + return skb; +} + +unsigned int ipvlan_nf_input(void *priv, struct sk_buff *skb, + const struct nf_hook_state *state) +{ + struct ipvl_addr *addr; + unsigned int len; + + addr = ipvlan_skb_to_addr(skb, skb->dev); + if (!addr) + goto out; + + skb->dev = addr->master->dev; + len = skb->len + ETH_HLEN; + ipvlan_count_rx(addr->master, len, true, false); +out: + return NF_ACCEPT; +} diff --git a/drivers/net/ipvlan/ipvlan_main.c b/drivers/net/ipvlan/ipvlan_main.c index 18b4e8c..f442eb3 100644 --- a/drivers/net/ipvlan/ipvlan_main.c +++ b/drivers/net/ipvlan/ipvlan_main.c @@ -9,24 +9,87 @@ #include "ipvlan.h" +static u32 ipvl_nf_hook_refcnt = 0; + +static struct nf_hook_ops ipvl_nfops[] __read_mostly = { + { + .hook = ipvlan_nf_input, + .pf = NFPROTO_IPV4, + .hooknum = NF_INET_LOCAL_IN, + .priority = INT_MAX, + }, + { + .hook = ipvlan_nf_input, + .pf = NFPROTO_IPV6, + .hooknum = NF_INET_LOCAL_IN, + .priority = INT_MAX, + }, +}; + +static struct l3mdev_ops ipvl_l3mdev_ops __read_mostly = { + .l3mdev_l3_rcv = ipvlan_l3_rcv, +}; + static void ipvlan_adjust_mtu(struct ipvl_dev *ipvlan, struct net_device *dev) { ipvlan->dev->mtu = dev->mtu - ipvlan->mtu_adj; } -static void ipvlan_set_port_mode(struct ipvl_port *port, u16 nval) +static int ipvlan_register_nf_hook(void) +{ + int err = 0; + + if (!ipvl_nf_hook_refcnt) { + err = _nf_register_hooks(ipvl_nfops, ARRAY_SIZE(ipvl_nfops)); + if (!err) + ipvl_nf_hook_refcnt = 1; + } else { + ipvl_nf_hook_refcnt++; + } + + return err; +} + +static void ipvlan_unregister_nf_hook(void) +{ + WARN_ON(!ipvl_nf_hook_refcnt); + + ipvl_nf_hook_refcnt--; + if (!ipvl_nf_hook_refcnt) + _nf_unregister_hooks(ipvl_nfops, ARRAY_SIZE(ipvl_nfops)); +} + +static int ipvlan_set_port_mode(struct ipvl_port *port, u16 nval) { struct ipvl_dev *ipvlan; + struct net_device *mdev = port->dev; + int err = 0; + ASSERT_RTNL(); if (port->mode != nval) { + if (nval == IPVLAN_MODE_L3S) { + /* New mode is L3S */ + err = ipvlan_register_nf_hook(); + if (!err) { + mdev->l3mdev_ops = &ipvl_l3mdev_ops; + mdev->priv_flags |= IFF_L3MDEV_MASTER; + } else + return err; + } else if (port->mode == IPVLAN_MODE_L3S) { + /* Old mode was L3S */ + mdev->priv_flags &= ~IFF_L3MDEV_MASTER; + ipvlan_unregister_nf_hook(); + mdev->l3mdev_ops = NULL; + } list_for_each_entry(ipvlan, &port->ipvlans, pnode) { - if (nval == IPVLAN_MODE_L3) + if (nval == IPVLAN_MODE_L3 || nval == IPVLAN_MODE_L3S) ipvlan->dev->flags |= IFF_NOARP; else ipvlan->dev->flags &= ~IFF_NOARP; } port->mode = nval; } + return err; } static int ipvlan_port_create(struct net_device *dev) @@ -74,6 +137,11 @@ static void ipvlan_port_destroy(struct net_device *dev) struct ipvl_port *port = ipvlan_port_get_rtnl(dev); dev->priv_flags &= ~IFF_IPVLAN_MASTER; + if (port->mode == IPVLAN_MODE_L3S) { + dev->priv_flags &= ~IFF_L3MDEV_MASTER; + ipvlan_unregister_nf_hook(); + dev->l3mdev_ops = NULL; + } netdev_rx_handler_unregister(dev); cancel_work_sync(&port->wq); __skb_queue_purge(&port->backlog); @@ -132,7 +200,8 @@ static int ipvlan_open(struct net_device *dev) struct net_device *phy_dev = ipvlan->phy_dev; struct ipvl_addr *addr; - if (ipvlan->port->mode == IPVLAN_MODE_L3) + if (ipvlan->port->mode == IPVLAN_MODE_L3 || + ipvlan->port->mode == IPVLAN_MODE_L3S) dev->flags |= IFF_NOARP; else dev->flags &= ~IFF_NOARP; @@ -372,13 +441,14 @@ static int ipvlan_nl_changelink(struct net_device *dev, { struct ipvl_dev *ipvlan = netdev_priv(dev); struct ipvl_port *port = ipvlan_port_get_rtnl(ipvlan->phy_dev); + int err = 0; if (data && data[IFLA_IPVLAN_MODE]) { u16 nmode = nla_get_u16(data[IFLA_IPVLAN_MODE]); - ipvlan_set_port_mode(port, nmode); + err = ipvlan_set_port_mode(port, nmode); } - return 0; + return err; } static size_t ipvlan_nl_getsize(const struct net_device *dev) @@ -473,10 +543,13 @@ static int ipvlan_link_new(struct net *src_net, struct net_device *dev, unregister_netdevice(dev); return err; } + err = ipvlan_set_port_mode(port, mode); + if (err) { + unregister_netdevice(dev); + return err; + } list_add_tail_rcu(&ipvlan->pnode, &port->ipvlans); - ipvlan_set_port_mode(port, mode); - netif_stacked_transfer_operstate(phy_dev, dev); return 0; } -- cgit v1.1