diff options
Diffstat (limited to 'net/openvswitch/actions.c')
-rw-r--r-- | net/openvswitch/actions.c | 1658 |
1 files changed, 1658 insertions, 0 deletions
diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c new file mode 100644 index 0000000000..fd66014d8a --- /dev/null +++ b/net/openvswitch/actions.c @@ -0,0 +1,1658 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2007-2017 Nicira, Inc. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/skbuff.h> +#include <linux/in.h> +#include <linux/ip.h> +#include <linux/openvswitch.h> +#include <linux/sctp.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <linux/in6.h> +#include <linux/if_arp.h> +#include <linux/if_vlan.h> + +#include <net/dst.h> +#include <net/gso.h> +#include <net/ip.h> +#include <net/ipv6.h> +#include <net/ip6_fib.h> +#include <net/checksum.h> +#include <net/dsfield.h> +#include <net/mpls.h> +#include <net/sctp/checksum.h> + +#include "datapath.h" +#include "drop.h" +#include "flow.h" +#include "conntrack.h" +#include "vport.h" +#include "flow_netlink.h" +#include "openvswitch_trace.h" + +struct deferred_action { + struct sk_buff *skb; + const struct nlattr *actions; + int actions_len; + + /* Store pkt_key clone when creating deferred action. */ + struct sw_flow_key pkt_key; +}; + +#define MAX_L2_LEN (VLAN_ETH_HLEN + 3 * MPLS_HLEN) +struct ovs_frag_data { + unsigned long dst; + struct vport *vport; + struct ovs_skb_cb cb; + __be16 inner_protocol; + u16 network_offset; /* valid only for MPLS */ + u16 vlan_tci; + __be16 vlan_proto; + unsigned int l2_len; + u8 mac_proto; + u8 l2_data[MAX_L2_LEN]; +}; + +static DEFINE_PER_CPU(struct ovs_frag_data, ovs_frag_data_storage); + +#define DEFERRED_ACTION_FIFO_SIZE 10 +#define OVS_RECURSION_LIMIT 5 +#define OVS_DEFERRED_ACTION_THRESHOLD (OVS_RECURSION_LIMIT - 2) +struct action_fifo { + int head; + int tail; + /* Deferred action fifo queue storage. */ + struct deferred_action fifo[DEFERRED_ACTION_FIFO_SIZE]; +}; + +struct action_flow_keys { + struct sw_flow_key key[OVS_DEFERRED_ACTION_THRESHOLD]; +}; + +static struct action_fifo __percpu *action_fifos; +static struct action_flow_keys __percpu *flow_keys; +static DEFINE_PER_CPU(int, exec_actions_level); + +/* Make a clone of the 'key', using the pre-allocated percpu 'flow_keys' + * space. Return NULL if out of key spaces. + */ +static struct sw_flow_key *clone_key(const struct sw_flow_key *key_) +{ + struct action_flow_keys *keys = this_cpu_ptr(flow_keys); + int level = this_cpu_read(exec_actions_level); + struct sw_flow_key *key = NULL; + + if (level <= OVS_DEFERRED_ACTION_THRESHOLD) { + key = &keys->key[level - 1]; + *key = *key_; + } + + return key; +} + +static void action_fifo_init(struct action_fifo *fifo) +{ + fifo->head = 0; + fifo->tail = 0; +} + +static bool action_fifo_is_empty(const struct action_fifo *fifo) +{ + return (fifo->head == fifo->tail); +} + +static struct deferred_action *action_fifo_get(struct action_fifo *fifo) +{ + if (action_fifo_is_empty(fifo)) + return NULL; + + return &fifo->fifo[fifo->tail++]; +} + +static struct deferred_action *action_fifo_put(struct action_fifo *fifo) +{ + if (fifo->head >= DEFERRED_ACTION_FIFO_SIZE - 1) + return NULL; + + return &fifo->fifo[fifo->head++]; +} + +/* Return true if fifo is not full */ +static struct deferred_action *add_deferred_actions(struct sk_buff *skb, + const struct sw_flow_key *key, + const struct nlattr *actions, + const int actions_len) +{ + struct action_fifo *fifo; + struct deferred_action *da; + + fifo = this_cpu_ptr(action_fifos); + da = action_fifo_put(fifo); + if (da) { + da->skb = skb; + da->actions = actions; + da->actions_len = actions_len; + da->pkt_key = *key; + } + + return da; +} + +static void invalidate_flow_key(struct sw_flow_key *key) +{ + key->mac_proto |= SW_FLOW_KEY_INVALID; +} + +static bool is_flow_key_valid(const struct sw_flow_key *key) +{ + return !(key->mac_proto & SW_FLOW_KEY_INVALID); +} + +static int clone_execute(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, + u32 recirc_id, + const struct nlattr *actions, int len, + bool last, bool clone_flow_key); + +static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, + const struct nlattr *attr, int len); + +static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key, + __be32 mpls_lse, __be16 mpls_ethertype, __u16 mac_len) +{ + int err; + + err = skb_mpls_push(skb, mpls_lse, mpls_ethertype, mac_len, !!mac_len); + if (err) + return err; + + if (!mac_len) + key->mac_proto = MAC_PROTO_NONE; + + invalidate_flow_key(key); + return 0; +} + +static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key, + const __be16 ethertype) +{ + int err; + + err = skb_mpls_pop(skb, ethertype, skb->mac_len, + ovs_key_mac_proto(key) == MAC_PROTO_ETHERNET); + if (err) + return err; + + if (ethertype == htons(ETH_P_TEB)) + key->mac_proto = MAC_PROTO_ETHERNET; + + invalidate_flow_key(key); + return 0; +} + +static int set_mpls(struct sk_buff *skb, struct sw_flow_key *flow_key, + const __be32 *mpls_lse, const __be32 *mask) +{ + struct mpls_shim_hdr *stack; + __be32 lse; + int err; + + if (!pskb_may_pull(skb, skb_network_offset(skb) + MPLS_HLEN)) + return -ENOMEM; + + stack = mpls_hdr(skb); + lse = OVS_MASKED(stack->label_stack_entry, *mpls_lse, *mask); + err = skb_mpls_update_lse(skb, lse); + if (err) + return err; + + flow_key->mpls.lse[0] = lse; + return 0; +} + +static int pop_vlan(struct sk_buff *skb, struct sw_flow_key *key) +{ + int err; + + err = skb_vlan_pop(skb); + if (skb_vlan_tag_present(skb)) { + invalidate_flow_key(key); + } else { + key->eth.vlan.tci = 0; + key->eth.vlan.tpid = 0; + } + return err; +} + +static int push_vlan(struct sk_buff *skb, struct sw_flow_key *key, + const struct ovs_action_push_vlan *vlan) +{ + if (skb_vlan_tag_present(skb)) { + invalidate_flow_key(key); + } else { + key->eth.vlan.tci = vlan->vlan_tci; + key->eth.vlan.tpid = vlan->vlan_tpid; + } + return skb_vlan_push(skb, vlan->vlan_tpid, + ntohs(vlan->vlan_tci) & ~VLAN_CFI_MASK); +} + +/* 'src' is already properly masked. */ +static void ether_addr_copy_masked(u8 *dst_, const u8 *src_, const u8 *mask_) +{ + u16 *dst = (u16 *)dst_; + const u16 *src = (const u16 *)src_; + const u16 *mask = (const u16 *)mask_; + + OVS_SET_MASKED(dst[0], src[0], mask[0]); + OVS_SET_MASKED(dst[1], src[1], mask[1]); + OVS_SET_MASKED(dst[2], src[2], mask[2]); +} + +static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key, + const struct ovs_key_ethernet *key, + const struct ovs_key_ethernet *mask) +{ + int err; + + err = skb_ensure_writable(skb, ETH_HLEN); + if (unlikely(err)) + return err; + + skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); + + ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src, + mask->eth_src); + ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst, + mask->eth_dst); + + skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2); + + ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source); + ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest); + return 0; +} + +/* pop_eth does not support VLAN packets as this action is never called + * for them. + */ +static int pop_eth(struct sk_buff *skb, struct sw_flow_key *key) +{ + int err; + + err = skb_eth_pop(skb); + if (err) + return err; + + /* safe right before invalidate_flow_key */ + key->mac_proto = MAC_PROTO_NONE; + invalidate_flow_key(key); + return 0; +} + +static int push_eth(struct sk_buff *skb, struct sw_flow_key *key, + const struct ovs_action_push_eth *ethh) +{ + int err; + + err = skb_eth_push(skb, ethh->addresses.eth_dst, + ethh->addresses.eth_src); + if (err) + return err; + + /* safe right before invalidate_flow_key */ + key->mac_proto = MAC_PROTO_ETHERNET; + invalidate_flow_key(key); + return 0; +} + +static int push_nsh(struct sk_buff *skb, struct sw_flow_key *key, + const struct nshhdr *nh) +{ + int err; + + err = nsh_push(skb, nh); + if (err) + return err; + + /* safe right before invalidate_flow_key */ + key->mac_proto = MAC_PROTO_NONE; + invalidate_flow_key(key); + return 0; +} + +static int pop_nsh(struct sk_buff *skb, struct sw_flow_key *key) +{ + int err; + + err = nsh_pop(skb); + if (err) + return err; + + /* safe right before invalidate_flow_key */ + if (skb->protocol == htons(ETH_P_TEB)) + key->mac_proto = MAC_PROTO_ETHERNET; + else + key->mac_proto = MAC_PROTO_NONE; + invalidate_flow_key(key); + return 0; +} + +static void update_ip_l4_checksum(struct sk_buff *skb, struct iphdr *nh, + __be32 addr, __be32 new_addr) +{ + int transport_len = skb->len - skb_transport_offset(skb); + + if (nh->frag_off & htons(IP_OFFSET)) + return; + + if (nh->protocol == IPPROTO_TCP) { + if (likely(transport_len >= sizeof(struct tcphdr))) + inet_proto_csum_replace4(&tcp_hdr(skb)->check, skb, + addr, new_addr, true); + } else if (nh->protocol == IPPROTO_UDP) { + if (likely(transport_len >= sizeof(struct udphdr))) { + struct udphdr *uh = udp_hdr(skb); + + if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { + inet_proto_csum_replace4(&uh->check, skb, + addr, new_addr, true); + if (!uh->check) + uh->check = CSUM_MANGLED_0; + } + } + } +} + +static void set_ip_addr(struct sk_buff *skb, struct iphdr *nh, + __be32 *addr, __be32 new_addr) +{ + update_ip_l4_checksum(skb, nh, *addr, new_addr); + csum_replace4(&nh->check, *addr, new_addr); + skb_clear_hash(skb); + ovs_ct_clear(skb, NULL); + *addr = new_addr; +} + +static void update_ipv6_checksum(struct sk_buff *skb, u8 l4_proto, + __be32 addr[4], const __be32 new_addr[4]) +{ + int transport_len = skb->len - skb_transport_offset(skb); + + if (l4_proto == NEXTHDR_TCP) { + if (likely(transport_len >= sizeof(struct tcphdr))) + inet_proto_csum_replace16(&tcp_hdr(skb)->check, skb, + addr, new_addr, true); + } else if (l4_proto == NEXTHDR_UDP) { + if (likely(transport_len >= sizeof(struct udphdr))) { + struct udphdr *uh = udp_hdr(skb); + + if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { + inet_proto_csum_replace16(&uh->check, skb, + addr, new_addr, true); + if (!uh->check) + uh->check = CSUM_MANGLED_0; + } + } + } else if (l4_proto == NEXTHDR_ICMP) { + if (likely(transport_len >= sizeof(struct icmp6hdr))) + inet_proto_csum_replace16(&icmp6_hdr(skb)->icmp6_cksum, + skb, addr, new_addr, true); + } +} + +static void mask_ipv6_addr(const __be32 old[4], const __be32 addr[4], + const __be32 mask[4], __be32 masked[4]) +{ + masked[0] = OVS_MASKED(old[0], addr[0], mask[0]); + masked[1] = OVS_MASKED(old[1], addr[1], mask[1]); + masked[2] = OVS_MASKED(old[2], addr[2], mask[2]); + masked[3] = OVS_MASKED(old[3], addr[3], mask[3]); +} + +static void set_ipv6_addr(struct sk_buff *skb, u8 l4_proto, + __be32 addr[4], const __be32 new_addr[4], + bool recalculate_csum) +{ + if (recalculate_csum) + update_ipv6_checksum(skb, l4_proto, addr, new_addr); + + skb_clear_hash(skb); + ovs_ct_clear(skb, NULL); + memcpy(addr, new_addr, sizeof(__be32[4])); +} + +static void set_ipv6_dsfield(struct sk_buff *skb, struct ipv6hdr *nh, u8 ipv6_tclass, u8 mask) +{ + u8 old_ipv6_tclass = ipv6_get_dsfield(nh); + + ipv6_tclass = OVS_MASKED(old_ipv6_tclass, ipv6_tclass, mask); + + if (skb->ip_summed == CHECKSUM_COMPLETE) + csum_replace(&skb->csum, (__force __wsum)(old_ipv6_tclass << 12), + (__force __wsum)(ipv6_tclass << 12)); + + ipv6_change_dsfield(nh, ~mask, ipv6_tclass); +} + +static void set_ipv6_fl(struct sk_buff *skb, struct ipv6hdr *nh, u32 fl, u32 mask) +{ + u32 ofl; + + ofl = nh->flow_lbl[0] << 16 | nh->flow_lbl[1] << 8 | nh->flow_lbl[2]; + fl = OVS_MASKED(ofl, fl, mask); + + /* Bits 21-24 are always unmasked, so this retains their values. */ + nh->flow_lbl[0] = (u8)(fl >> 16); + nh->flow_lbl[1] = (u8)(fl >> 8); + nh->flow_lbl[2] = (u8)fl; + + if (skb->ip_summed == CHECKSUM_COMPLETE) + csum_replace(&skb->csum, (__force __wsum)htonl(ofl), (__force __wsum)htonl(fl)); +} + +static void set_ipv6_ttl(struct sk_buff *skb, struct ipv6hdr *nh, u8 new_ttl, u8 mask) +{ + new_ttl = OVS_MASKED(nh->hop_limit, new_ttl, mask); + + if (skb->ip_summed == CHECKSUM_COMPLETE) + csum_replace(&skb->csum, (__force __wsum)(nh->hop_limit << 8), + (__force __wsum)(new_ttl << 8)); + nh->hop_limit = new_ttl; +} + +static void set_ip_ttl(struct sk_buff *skb, struct iphdr *nh, u8 new_ttl, + u8 mask) +{ + new_ttl = OVS_MASKED(nh->ttl, new_ttl, mask); + + csum_replace2(&nh->check, htons(nh->ttl << 8), htons(new_ttl << 8)); + nh->ttl = new_ttl; +} + +static int set_ipv4(struct sk_buff *skb, struct sw_flow_key *flow_key, + const struct ovs_key_ipv4 *key, + const struct ovs_key_ipv4 *mask) +{ + struct iphdr *nh; + __be32 new_addr; + int err; + + err = skb_ensure_writable(skb, skb_network_offset(skb) + + sizeof(struct iphdr)); + if (unlikely(err)) + return err; + + nh = ip_hdr(skb); + + /* Setting an IP addresses is typically only a side effect of + * matching on them in the current userspace implementation, so it + * makes sense to check if the value actually changed. + */ + if (mask->ipv4_src) { + new_addr = OVS_MASKED(nh->saddr, key->ipv4_src, mask->ipv4_src); + + if (unlikely(new_addr != nh->saddr)) { + set_ip_addr(skb, nh, &nh->saddr, new_addr); + flow_key->ipv4.addr.src = new_addr; + } + } + if (mask->ipv4_dst) { + new_addr = OVS_MASKED(nh->daddr, key->ipv4_dst, mask->ipv4_dst); + + if (unlikely(new_addr != nh->daddr)) { + set_ip_addr(skb, nh, &nh->daddr, new_addr); + flow_key->ipv4.addr.dst = new_addr; + } + } + if (mask->ipv4_tos) { + ipv4_change_dsfield(nh, ~mask->ipv4_tos, key->ipv4_tos); + flow_key->ip.tos = nh->tos; + } + if (mask->ipv4_ttl) { + set_ip_ttl(skb, nh, key->ipv4_ttl, mask->ipv4_ttl); + flow_key->ip.ttl = nh->ttl; + } + + return 0; +} + +static bool is_ipv6_mask_nonzero(const __be32 addr[4]) +{ + return !!(addr[0] | addr[1] | addr[2] | addr[3]); +} + +static int set_ipv6(struct sk_buff *skb, struct sw_flow_key *flow_key, + const struct ovs_key_ipv6 *key, + const struct ovs_key_ipv6 *mask) +{ + struct ipv6hdr *nh; + int err; + + err = skb_ensure_writable(skb, skb_network_offset(skb) + + sizeof(struct ipv6hdr)); + if (unlikely(err)) + return err; + + nh = ipv6_hdr(skb); + + /* Setting an IP addresses is typically only a side effect of + * matching on them in the current userspace implementation, so it + * makes sense to check if the value actually changed. + */ + if (is_ipv6_mask_nonzero(mask->ipv6_src)) { + __be32 *saddr = (__be32 *)&nh->saddr; + __be32 masked[4]; + + mask_ipv6_addr(saddr, key->ipv6_src, mask->ipv6_src, masked); + + if (unlikely(memcmp(saddr, masked, sizeof(masked)))) { + set_ipv6_addr(skb, flow_key->ip.proto, saddr, masked, + true); + memcpy(&flow_key->ipv6.addr.src, masked, + sizeof(flow_key->ipv6.addr.src)); + } + } + if (is_ipv6_mask_nonzero(mask->ipv6_dst)) { + unsigned int offset = 0; + int flags = IP6_FH_F_SKIP_RH; + bool recalc_csum = true; + __be32 *daddr = (__be32 *)&nh->daddr; + __be32 masked[4]; + + mask_ipv6_addr(daddr, key->ipv6_dst, mask->ipv6_dst, masked); + + if (unlikely(memcmp(daddr, masked, sizeof(masked)))) { + if (ipv6_ext_hdr(nh->nexthdr)) + recalc_csum = (ipv6_find_hdr(skb, &offset, + NEXTHDR_ROUTING, + NULL, &flags) + != NEXTHDR_ROUTING); + + set_ipv6_addr(skb, flow_key->ip.proto, daddr, masked, + recalc_csum); + memcpy(&flow_key->ipv6.addr.dst, masked, + sizeof(flow_key->ipv6.addr.dst)); + } + } + if (mask->ipv6_tclass) { + set_ipv6_dsfield(skb, nh, key->ipv6_tclass, mask->ipv6_tclass); + flow_key->ip.tos = ipv6_get_dsfield(nh); + } + if (mask->ipv6_label) { + set_ipv6_fl(skb, nh, ntohl(key->ipv6_label), + ntohl(mask->ipv6_label)); + flow_key->ipv6.label = + *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); + } + if (mask->ipv6_hlimit) { + set_ipv6_ttl(skb, nh, key->ipv6_hlimit, mask->ipv6_hlimit); + flow_key->ip.ttl = nh->hop_limit; + } + return 0; +} + +static int set_nsh(struct sk_buff *skb, struct sw_flow_key *flow_key, + const struct nlattr *a) +{ + struct nshhdr *nh; + size_t length; + int err; + u8 flags; + u8 ttl; + int i; + + struct ovs_key_nsh key; + struct ovs_key_nsh mask; + + err = nsh_key_from_nlattr(a, &key, &mask); + if (err) + return err; + + /* Make sure the NSH base header is there */ + if (!pskb_may_pull(skb, skb_network_offset(skb) + NSH_BASE_HDR_LEN)) + return -ENOMEM; + + nh = nsh_hdr(skb); + length = nsh_hdr_len(nh); + + /* Make sure the whole NSH header is there */ + err = skb_ensure_writable(skb, skb_network_offset(skb) + + length); + if (unlikely(err)) + return err; + + nh = nsh_hdr(skb); + skb_postpull_rcsum(skb, nh, length); + flags = nsh_get_flags(nh); + flags = OVS_MASKED(flags, key.base.flags, mask.base.flags); + flow_key->nsh.base.flags = flags; + ttl = nsh_get_ttl(nh); + ttl = OVS_MASKED(ttl, key.base.ttl, mask.base.ttl); + flow_key->nsh.base.ttl = ttl; + nsh_set_flags_and_ttl(nh, flags, ttl); + nh->path_hdr = OVS_MASKED(nh->path_hdr, key.base.path_hdr, + mask.base.path_hdr); + flow_key->nsh.base.path_hdr = nh->path_hdr; + switch (nh->mdtype) { + case NSH_M_TYPE1: + for (i = 0; i < NSH_MD1_CONTEXT_SIZE; i++) { + nh->md1.context[i] = + OVS_MASKED(nh->md1.context[i], key.context[i], + mask.context[i]); + } + memcpy(flow_key->nsh.context, nh->md1.context, + sizeof(nh->md1.context)); + break; + case NSH_M_TYPE2: + memset(flow_key->nsh.context, 0, + sizeof(flow_key->nsh.context)); + break; + default: + return -EINVAL; + } + skb_postpush_rcsum(skb, nh, length); + return 0; +} + +/* Must follow skb_ensure_writable() since that can move the skb data. */ +static void set_tp_port(struct sk_buff *skb, __be16 *port, + __be16 new_port, __sum16 *check) +{ + ovs_ct_clear(skb, NULL); + inet_proto_csum_replace2(check, skb, *port, new_port, false); + *port = new_port; +} + +static int set_udp(struct sk_buff *skb, struct sw_flow_key *flow_key, + const struct ovs_key_udp *key, + const struct ovs_key_udp *mask) +{ + struct udphdr *uh; + __be16 src, dst; + int err; + + err = skb_ensure_writable(skb, skb_transport_offset(skb) + + sizeof(struct udphdr)); + if (unlikely(err)) + return err; + + uh = udp_hdr(skb); + /* Either of the masks is non-zero, so do not bother checking them. */ + src = OVS_MASKED(uh->source, key->udp_src, mask->udp_src); + dst = OVS_MASKED(uh->dest, key->udp_dst, mask->udp_dst); + + if (uh->check && skb->ip_summed != CHECKSUM_PARTIAL) { + if (likely(src != uh->source)) { + set_tp_port(skb, &uh->source, src, &uh->check); + flow_key->tp.src = src; + } + if (likely(dst != uh->dest)) { + set_tp_port(skb, &uh->dest, dst, &uh->check); + flow_key->tp.dst = dst; + } + + if (unlikely(!uh->check)) + uh->check = CSUM_MANGLED_0; + } else { + uh->source = src; + uh->dest = dst; + flow_key->tp.src = src; + flow_key->tp.dst = dst; + ovs_ct_clear(skb, NULL); + } + + skb_clear_hash(skb); + + return 0; +} + +static int set_tcp(struct sk_buff *skb, struct sw_flow_key *flow_key, + const struct ovs_key_tcp *key, + const struct ovs_key_tcp *mask) +{ + struct tcphdr *th; + __be16 src, dst; + int err; + + err = skb_ensure_writable(skb, skb_transport_offset(skb) + + sizeof(struct tcphdr)); + if (unlikely(err)) + return err; + + th = tcp_hdr(skb); + src = OVS_MASKED(th->source, key->tcp_src, mask->tcp_src); + if (likely(src != th->source)) { + set_tp_port(skb, &th->source, src, &th->check); + flow_key->tp.src = src; + } + dst = OVS_MASKED(th->dest, key->tcp_dst, mask->tcp_dst); + if (likely(dst != th->dest)) { + set_tp_port(skb, &th->dest, dst, &th->check); + flow_key->tp.dst = dst; + } + skb_clear_hash(skb); + + return 0; +} + +static int set_sctp(struct sk_buff *skb, struct sw_flow_key *flow_key, + const struct ovs_key_sctp *key, + const struct ovs_key_sctp *mask) +{ + unsigned int sctphoff = skb_transport_offset(skb); + struct sctphdr *sh; + __le32 old_correct_csum, new_csum, old_csum; + int err; + + err = skb_ensure_writable(skb, sctphoff + sizeof(struct sctphdr)); + if (unlikely(err)) + return err; + + sh = sctp_hdr(skb); + old_csum = sh->checksum; + old_correct_csum = sctp_compute_cksum(skb, sctphoff); + + sh->source = OVS_MASKED(sh->source, key->sctp_src, mask->sctp_src); + sh->dest = OVS_MASKED(sh->dest, key->sctp_dst, mask->sctp_dst); + + new_csum = sctp_compute_cksum(skb, sctphoff); + + /* Carry any checksum errors through. */ + sh->checksum = old_csum ^ old_correct_csum ^ new_csum; + + skb_clear_hash(skb); + ovs_ct_clear(skb, NULL); + + flow_key->tp.src = sh->source; + flow_key->tp.dst = sh->dest; + + return 0; +} + +static int ovs_vport_output(struct net *net, struct sock *sk, + struct sk_buff *skb) +{ + struct ovs_frag_data *data = this_cpu_ptr(&ovs_frag_data_storage); + struct vport *vport = data->vport; + + if (skb_cow_head(skb, data->l2_len) < 0) { + kfree_skb_reason(skb, SKB_DROP_REASON_NOMEM); + return -ENOMEM; + } + + __skb_dst_copy(skb, data->dst); + *OVS_CB(skb) = data->cb; + skb->inner_protocol = data->inner_protocol; + if (data->vlan_tci & VLAN_CFI_MASK) + __vlan_hwaccel_put_tag(skb, data->vlan_proto, data->vlan_tci & ~VLAN_CFI_MASK); + else + __vlan_hwaccel_clear_tag(skb); + + /* Reconstruct the MAC header. */ + skb_push(skb, data->l2_len); + memcpy(skb->data, &data->l2_data, data->l2_len); + skb_postpush_rcsum(skb, skb->data, data->l2_len); + skb_reset_mac_header(skb); + + if (eth_p_mpls(skb->protocol)) { + skb->inner_network_header = skb->network_header; + skb_set_network_header(skb, data->network_offset); + skb_reset_mac_len(skb); + } + + ovs_vport_send(vport, skb, data->mac_proto); + return 0; +} + +static unsigned int +ovs_dst_get_mtu(const struct dst_entry *dst) +{ + return dst->dev->mtu; +} + +static struct dst_ops ovs_dst_ops = { + .family = AF_UNSPEC, + .mtu = ovs_dst_get_mtu, +}; + +/* prepare_frag() is called once per (larger-than-MTU) frame; its inverse is + * ovs_vport_output(), which is called once per fragmented packet. + */ +static void prepare_frag(struct vport *vport, struct sk_buff *skb, + u16 orig_network_offset, u8 mac_proto) +{ + unsigned int hlen = skb_network_offset(skb); + struct ovs_frag_data *data; + + data = this_cpu_ptr(&ovs_frag_data_storage); + data->dst = skb->_skb_refdst; + data->vport = vport; + data->cb = *OVS_CB(skb); + data->inner_protocol = skb->inner_protocol; + data->network_offset = orig_network_offset; + if (skb_vlan_tag_present(skb)) + data->vlan_tci = skb_vlan_tag_get(skb) | VLAN_CFI_MASK; + else + data->vlan_tci = 0; + data->vlan_proto = skb->vlan_proto; + data->mac_proto = mac_proto; + data->l2_len = hlen; + memcpy(&data->l2_data, skb->data, hlen); + + memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); + skb_pull(skb, hlen); +} + +static void ovs_fragment(struct net *net, struct vport *vport, + struct sk_buff *skb, u16 mru, + struct sw_flow_key *key) +{ + enum ovs_drop_reason reason; + u16 orig_network_offset = 0; + + if (eth_p_mpls(skb->protocol)) { + orig_network_offset = skb_network_offset(skb); + skb->network_header = skb->inner_network_header; + } + + if (skb_network_offset(skb) > MAX_L2_LEN) { + OVS_NLERR(1, "L2 header too long to fragment"); + reason = OVS_DROP_FRAG_L2_TOO_LONG; + goto err; + } + + if (key->eth.type == htons(ETH_P_IP)) { + struct rtable ovs_rt = { 0 }; + unsigned long orig_dst; + + prepare_frag(vport, skb, orig_network_offset, + ovs_key_mac_proto(key)); + dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1, + DST_OBSOLETE_NONE, DST_NOCOUNT); + ovs_rt.dst.dev = vport->dev; + + orig_dst = skb->_skb_refdst; + skb_dst_set_noref(skb, &ovs_rt.dst); + IPCB(skb)->frag_max_size = mru; + + ip_do_fragment(net, skb->sk, skb, ovs_vport_output); + refdst_drop(orig_dst); + } else if (key->eth.type == htons(ETH_P_IPV6)) { + unsigned long orig_dst; + struct rt6_info ovs_rt; + + prepare_frag(vport, skb, orig_network_offset, + ovs_key_mac_proto(key)); + memset(&ovs_rt, 0, sizeof(ovs_rt)); + dst_init(&ovs_rt.dst, &ovs_dst_ops, NULL, 1, + DST_OBSOLETE_NONE, DST_NOCOUNT); + ovs_rt.dst.dev = vport->dev; + + orig_dst = skb->_skb_refdst; + skb_dst_set_noref(skb, &ovs_rt.dst); + IP6CB(skb)->frag_max_size = mru; + + ipv6_stub->ipv6_fragment(net, skb->sk, skb, ovs_vport_output); + refdst_drop(orig_dst); + } else { + WARN_ONCE(1, "Failed fragment ->%s: eth=%04x, MRU=%d, MTU=%d.", + ovs_vport_name(vport), ntohs(key->eth.type), mru, + vport->dev->mtu); + reason = OVS_DROP_FRAG_INVALID_PROTO; + goto err; + } + + return; +err: + ovs_kfree_skb_reason(skb, reason); +} + +static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port, + struct sw_flow_key *key) +{ + struct vport *vport = ovs_vport_rcu(dp, out_port); + + if (likely(vport && netif_carrier_ok(vport->dev))) { + u16 mru = OVS_CB(skb)->mru; + u32 cutlen = OVS_CB(skb)->cutlen; + + if (unlikely(cutlen > 0)) { + if (skb->len - cutlen > ovs_mac_header_len(key)) + pskb_trim(skb, skb->len - cutlen); + else + pskb_trim(skb, ovs_mac_header_len(key)); + } + + if (likely(!mru || + (skb->len <= mru + vport->dev->hard_header_len))) { + ovs_vport_send(vport, skb, ovs_key_mac_proto(key)); + } else if (mru <= vport->dev->mtu) { + struct net *net = read_pnet(&dp->net); + + ovs_fragment(net, vport, skb, mru, key); + } else { + kfree_skb_reason(skb, SKB_DROP_REASON_PKT_TOO_BIG); + } + } else { + kfree_skb_reason(skb, SKB_DROP_REASON_DEV_READY); + } +} + +static int output_userspace(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, const struct nlattr *attr, + const struct nlattr *actions, int actions_len, + uint32_t cutlen) +{ + struct dp_upcall_info upcall; + const struct nlattr *a; + int rem; + + memset(&upcall, 0, sizeof(upcall)); + upcall.cmd = OVS_PACKET_CMD_ACTION; + upcall.mru = OVS_CB(skb)->mru; + + for (a = nla_data(attr), rem = nla_len(attr); rem > 0; + a = nla_next(a, &rem)) { + switch (nla_type(a)) { + case OVS_USERSPACE_ATTR_USERDATA: + upcall.userdata = a; + break; + + case OVS_USERSPACE_ATTR_PID: + if (dp->user_features & + OVS_DP_F_DISPATCH_UPCALL_PER_CPU) + upcall.portid = + ovs_dp_get_upcall_portid(dp, + smp_processor_id()); + else + upcall.portid = nla_get_u32(a); + break; + + case OVS_USERSPACE_ATTR_EGRESS_TUN_PORT: { + /* Get out tunnel info. */ + struct vport *vport; + + vport = ovs_vport_rcu(dp, nla_get_u32(a)); + if (vport) { + int err; + + err = dev_fill_metadata_dst(vport->dev, skb); + if (!err) + upcall.egress_tun_info = skb_tunnel_info(skb); + } + + break; + } + + case OVS_USERSPACE_ATTR_ACTIONS: { + /* Include actions. */ + upcall.actions = actions; + upcall.actions_len = actions_len; + break; + } + + } /* End of switch. */ + } + + return ovs_dp_upcall(dp, skb, key, &upcall, cutlen); +} + +static int dec_ttl_exception_handler(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, + const struct nlattr *attr) +{ + /* The first attribute is always 'OVS_DEC_TTL_ATTR_ACTION'. */ + struct nlattr *actions = nla_data(attr); + + if (nla_len(actions)) + return clone_execute(dp, skb, key, 0, nla_data(actions), + nla_len(actions), true, false); + + ovs_kfree_skb_reason(skb, OVS_DROP_IP_TTL); + return 0; +} + +/* When 'last' is true, sample() should always consume the 'skb'. + * Otherwise, sample() should keep 'skb' intact regardless what + * actions are executed within sample(). + */ +static int sample(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, const struct nlattr *attr, + bool last) +{ + struct nlattr *actions; + struct nlattr *sample_arg; + int rem = nla_len(attr); + const struct sample_arg *arg; + bool clone_flow_key; + + /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */ + sample_arg = nla_data(attr); + arg = nla_data(sample_arg); + actions = nla_next(sample_arg, &rem); + + if ((arg->probability != U32_MAX) && + (!arg->probability || get_random_u32() > arg->probability)) { + if (last) + ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION); + return 0; + } + + clone_flow_key = !arg->exec; + return clone_execute(dp, skb, key, 0, actions, rem, last, + clone_flow_key); +} + +/* When 'last' is true, clone() should always consume the 'skb'. + * Otherwise, clone() should keep 'skb' intact regardless what + * actions are executed within clone(). + */ +static int clone(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, const struct nlattr *attr, + bool last) +{ + struct nlattr *actions; + struct nlattr *clone_arg; + int rem = nla_len(attr); + bool dont_clone_flow_key; + + /* The first action is always 'OVS_CLONE_ATTR_EXEC'. */ + clone_arg = nla_data(attr); + dont_clone_flow_key = nla_get_u32(clone_arg); + actions = nla_next(clone_arg, &rem); + + return clone_execute(dp, skb, key, 0, actions, rem, last, + !dont_clone_flow_key); +} + +static void execute_hash(struct sk_buff *skb, struct sw_flow_key *key, + const struct nlattr *attr) +{ + struct ovs_action_hash *hash_act = nla_data(attr); + u32 hash = 0; + + if (hash_act->hash_alg == OVS_HASH_ALG_L4) { + /* OVS_HASH_ALG_L4 hasing type. */ + hash = skb_get_hash(skb); + } else if (hash_act->hash_alg == OVS_HASH_ALG_SYM_L4) { + /* OVS_HASH_ALG_SYM_L4 hashing type. NOTE: this doesn't + * extend past an encapsulated header. + */ + hash = __skb_get_hash_symmetric(skb); + } + + hash = jhash_1word(hash, hash_act->hash_basis); + if (!hash) + hash = 0x1; + + key->ovs_flow_hash = hash; +} + +static int execute_set_action(struct sk_buff *skb, + struct sw_flow_key *flow_key, + const struct nlattr *a) +{ + /* Only tunnel set execution is supported without a mask. */ + if (nla_type(a) == OVS_KEY_ATTR_TUNNEL_INFO) { + struct ovs_tunnel_info *tun = nla_data(a); + + skb_dst_drop(skb); + dst_hold((struct dst_entry *)tun->tun_dst); + skb_dst_set(skb, (struct dst_entry *)tun->tun_dst); + return 0; + } + + return -EINVAL; +} + +/* Mask is at the midpoint of the data. */ +#define get_mask(a, type) ((const type)nla_data(a) + 1) + +static int execute_masked_set_action(struct sk_buff *skb, + struct sw_flow_key *flow_key, + const struct nlattr *a) +{ + int err = 0; + + switch (nla_type(a)) { + case OVS_KEY_ATTR_PRIORITY: + OVS_SET_MASKED(skb->priority, nla_get_u32(a), + *get_mask(a, u32 *)); + flow_key->phy.priority = skb->priority; + break; + + case OVS_KEY_ATTR_SKB_MARK: + OVS_SET_MASKED(skb->mark, nla_get_u32(a), *get_mask(a, u32 *)); + flow_key->phy.skb_mark = skb->mark; + break; + + case OVS_KEY_ATTR_TUNNEL_INFO: + /* Masked data not supported for tunnel. */ + err = -EINVAL; + break; + + case OVS_KEY_ATTR_ETHERNET: + err = set_eth_addr(skb, flow_key, nla_data(a), + get_mask(a, struct ovs_key_ethernet *)); + break; + + case OVS_KEY_ATTR_NSH: + err = set_nsh(skb, flow_key, a); + break; + + case OVS_KEY_ATTR_IPV4: + err = set_ipv4(skb, flow_key, nla_data(a), + get_mask(a, struct ovs_key_ipv4 *)); + break; + + case OVS_KEY_ATTR_IPV6: + err = set_ipv6(skb, flow_key, nla_data(a), + get_mask(a, struct ovs_key_ipv6 *)); + break; + + case OVS_KEY_ATTR_TCP: + err = set_tcp(skb, flow_key, nla_data(a), + get_mask(a, struct ovs_key_tcp *)); + break; + + case OVS_KEY_ATTR_UDP: + err = set_udp(skb, flow_key, nla_data(a), + get_mask(a, struct ovs_key_udp *)); + break; + + case OVS_KEY_ATTR_SCTP: + err = set_sctp(skb, flow_key, nla_data(a), + get_mask(a, struct ovs_key_sctp *)); + break; + + case OVS_KEY_ATTR_MPLS: + err = set_mpls(skb, flow_key, nla_data(a), get_mask(a, + __be32 *)); + break; + + case OVS_KEY_ATTR_CT_STATE: + case OVS_KEY_ATTR_CT_ZONE: + case OVS_KEY_ATTR_CT_MARK: + case OVS_KEY_ATTR_CT_LABELS: + case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4: + case OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6: + err = -EINVAL; + break; + } + + return err; +} + +static int execute_recirc(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, + const struct nlattr *a, bool last) +{ + u32 recirc_id; + + if (!is_flow_key_valid(key)) { + int err; + + err = ovs_flow_key_update(skb, key); + if (err) + return err; + } + BUG_ON(!is_flow_key_valid(key)); + + recirc_id = nla_get_u32(a); + return clone_execute(dp, skb, key, recirc_id, NULL, 0, last, true); +} + +static int execute_check_pkt_len(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, + const struct nlattr *attr, bool last) +{ + struct ovs_skb_cb *ovs_cb = OVS_CB(skb); + const struct nlattr *actions, *cpl_arg; + int len, max_len, rem = nla_len(attr); + const struct check_pkt_len_arg *arg; + bool clone_flow_key; + + /* The first netlink attribute in 'attr' is always + * 'OVS_CHECK_PKT_LEN_ATTR_ARG'. + */ + cpl_arg = nla_data(attr); + arg = nla_data(cpl_arg); + + len = ovs_cb->mru ? ovs_cb->mru + skb->mac_len : skb->len; + max_len = arg->pkt_len; + + if ((skb_is_gso(skb) && skb_gso_validate_mac_len(skb, max_len)) || + len <= max_len) { + /* Second netlink attribute in 'attr' is always + * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_LESS_EQUAL'. + */ + actions = nla_next(cpl_arg, &rem); + clone_flow_key = !arg->exec_for_lesser_equal; + } else { + /* Third netlink attribute in 'attr' is always + * 'OVS_CHECK_PKT_LEN_ATTR_ACTIONS_IF_GREATER'. + */ + actions = nla_next(cpl_arg, &rem); + actions = nla_next(actions, &rem); + clone_flow_key = !arg->exec_for_greater; + } + + return clone_execute(dp, skb, key, 0, nla_data(actions), + nla_len(actions), last, clone_flow_key); +} + +static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key) +{ + int err; + + if (skb->protocol == htons(ETH_P_IPV6)) { + struct ipv6hdr *nh; + + err = skb_ensure_writable(skb, skb_network_offset(skb) + + sizeof(*nh)); + if (unlikely(err)) + return err; + + nh = ipv6_hdr(skb); + + if (nh->hop_limit <= 1) + return -EHOSTUNREACH; + + key->ip.ttl = --nh->hop_limit; + } else if (skb->protocol == htons(ETH_P_IP)) { + struct iphdr *nh; + u8 old_ttl; + + err = skb_ensure_writable(skb, skb_network_offset(skb) + + sizeof(*nh)); + if (unlikely(err)) + return err; + + nh = ip_hdr(skb); + if (nh->ttl <= 1) + return -EHOSTUNREACH; + + old_ttl = nh->ttl--; + csum_replace2(&nh->check, htons(old_ttl << 8), + htons(nh->ttl << 8)); + key->ip.ttl = nh->ttl; + } + return 0; +} + +/* Execute a list of actions against 'skb'. */ +static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, + const struct nlattr *attr, int len) +{ + const struct nlattr *a; + int rem; + + for (a = attr, rem = len; rem > 0; + a = nla_next(a, &rem)) { + int err = 0; + + if (trace_ovs_do_execute_action_enabled()) + trace_ovs_do_execute_action(dp, skb, key, a, rem); + + /* Actions that rightfully have to consume the skb should do it + * and return directly. + */ + switch (nla_type(a)) { + case OVS_ACTION_ATTR_OUTPUT: { + int port = nla_get_u32(a); + struct sk_buff *clone; + + /* Every output action needs a separate clone + * of 'skb', In case the output action is the + * last action, cloning can be avoided. + */ + if (nla_is_last(a, rem)) { + do_output(dp, skb, port, key); + /* 'skb' has been used for output. + */ + return 0; + } + + clone = skb_clone(skb, GFP_ATOMIC); + if (clone) + do_output(dp, clone, port, key); + OVS_CB(skb)->cutlen = 0; + break; + } + + case OVS_ACTION_ATTR_TRUNC: { + struct ovs_action_trunc *trunc = nla_data(a); + + if (skb->len > trunc->max_len) + OVS_CB(skb)->cutlen = skb->len - trunc->max_len; + break; + } + + case OVS_ACTION_ATTR_USERSPACE: + output_userspace(dp, skb, key, a, attr, + len, OVS_CB(skb)->cutlen); + OVS_CB(skb)->cutlen = 0; + if (nla_is_last(a, rem)) { + consume_skb(skb); + return 0; + } + break; + + case OVS_ACTION_ATTR_HASH: + execute_hash(skb, key, a); + break; + + case OVS_ACTION_ATTR_PUSH_MPLS: { + struct ovs_action_push_mpls *mpls = nla_data(a); + + err = push_mpls(skb, key, mpls->mpls_lse, + mpls->mpls_ethertype, skb->mac_len); + break; + } + case OVS_ACTION_ATTR_ADD_MPLS: { + struct ovs_action_add_mpls *mpls = nla_data(a); + __u16 mac_len = 0; + + if (mpls->tun_flags & OVS_MPLS_L3_TUNNEL_FLAG_MASK) + mac_len = skb->mac_len; + + err = push_mpls(skb, key, mpls->mpls_lse, + mpls->mpls_ethertype, mac_len); + break; + } + case OVS_ACTION_ATTR_POP_MPLS: + err = pop_mpls(skb, key, nla_get_be16(a)); + break; + + case OVS_ACTION_ATTR_PUSH_VLAN: + err = push_vlan(skb, key, nla_data(a)); + break; + + case OVS_ACTION_ATTR_POP_VLAN: + err = pop_vlan(skb, key); + break; + + case OVS_ACTION_ATTR_RECIRC: { + bool last = nla_is_last(a, rem); + + err = execute_recirc(dp, skb, key, a, last); + if (last) { + /* If this is the last action, the skb has + * been consumed or freed. + * Return immediately. + */ + return err; + } + break; + } + + case OVS_ACTION_ATTR_SET: + err = execute_set_action(skb, key, nla_data(a)); + break; + + case OVS_ACTION_ATTR_SET_MASKED: + case OVS_ACTION_ATTR_SET_TO_MASKED: + err = execute_masked_set_action(skb, key, nla_data(a)); + break; + + case OVS_ACTION_ATTR_SAMPLE: { + bool last = nla_is_last(a, rem); + + err = sample(dp, skb, key, a, last); + if (last) + return err; + + break; + } + + case OVS_ACTION_ATTR_CT: + if (!is_flow_key_valid(key)) { + err = ovs_flow_key_update(skb, key); + if (err) + return err; + } + + err = ovs_ct_execute(ovs_dp_get_net(dp), skb, key, + nla_data(a)); + + /* Hide stolen IP fragments from user space. */ + if (err) + return err == -EINPROGRESS ? 0 : err; + break; + + case OVS_ACTION_ATTR_CT_CLEAR: + err = ovs_ct_clear(skb, key); + break; + + case OVS_ACTION_ATTR_PUSH_ETH: + err = push_eth(skb, key, nla_data(a)); + break; + + case OVS_ACTION_ATTR_POP_ETH: + err = pop_eth(skb, key); + break; + + case OVS_ACTION_ATTR_PUSH_NSH: { + u8 buffer[NSH_HDR_MAX_LEN]; + struct nshhdr *nh = (struct nshhdr *)buffer; + + err = nsh_hdr_from_nlattr(nla_data(a), nh, + NSH_HDR_MAX_LEN); + if (unlikely(err)) + break; + err = push_nsh(skb, key, nh); + break; + } + + case OVS_ACTION_ATTR_POP_NSH: + err = pop_nsh(skb, key); + break; + + case OVS_ACTION_ATTR_METER: + if (ovs_meter_execute(dp, skb, key, nla_get_u32(a))) { + ovs_kfree_skb_reason(skb, OVS_DROP_METER); + return 0; + } + break; + + case OVS_ACTION_ATTR_CLONE: { + bool last = nla_is_last(a, rem); + + err = clone(dp, skb, key, a, last); + if (last) + return err; + + break; + } + + case OVS_ACTION_ATTR_CHECK_PKT_LEN: { + bool last = nla_is_last(a, rem); + + err = execute_check_pkt_len(dp, skb, key, a, last); + if (last) + return err; + + break; + } + + case OVS_ACTION_ATTR_DEC_TTL: + err = execute_dec_ttl(skb, key); + if (err == -EHOSTUNREACH) + return dec_ttl_exception_handler(dp, skb, + key, a); + break; + + case OVS_ACTION_ATTR_DROP: { + enum ovs_drop_reason reason = nla_get_u32(a) + ? OVS_DROP_EXPLICIT_WITH_ERROR + : OVS_DROP_EXPLICIT; + + ovs_kfree_skb_reason(skb, reason); + return 0; + } + } + + if (unlikely(err)) { + ovs_kfree_skb_reason(skb, OVS_DROP_ACTION_ERROR); + return err; + } + } + + ovs_kfree_skb_reason(skb, OVS_DROP_LAST_ACTION); + return 0; +} + +/* Execute the actions on the clone of the packet. The effect of the + * execution does not affect the original 'skb' nor the original 'key'. + * + * The execution may be deferred in case the actions can not be executed + * immediately. + */ +static int clone_execute(struct datapath *dp, struct sk_buff *skb, + struct sw_flow_key *key, u32 recirc_id, + const struct nlattr *actions, int len, + bool last, bool clone_flow_key) +{ + struct deferred_action *da; + struct sw_flow_key *clone; + + skb = last ? skb : skb_clone(skb, GFP_ATOMIC); + if (!skb) { + /* Out of memory, skip this action. + */ + return 0; + } + + /* When clone_flow_key is false, the 'key' will not be change + * by the actions, then the 'key' can be used directly. + * Otherwise, try to clone key from the next recursion level of + * 'flow_keys'. If clone is successful, execute the actions + * without deferring. + */ + clone = clone_flow_key ? clone_key(key) : key; + if (clone) { + int err = 0; + + if (actions) { /* Sample action */ + if (clone_flow_key) + __this_cpu_inc(exec_actions_level); + + err = do_execute_actions(dp, skb, clone, + actions, len); + + if (clone_flow_key) + __this_cpu_dec(exec_actions_level); + } else { /* Recirc action */ + clone->recirc_id = recirc_id; + ovs_dp_process_packet(skb, clone); + } + return err; + } + + /* Out of 'flow_keys' space. Defer actions */ + da = add_deferred_actions(skb, key, actions, len); + if (da) { + if (!actions) { /* Recirc action */ + key = &da->pkt_key; + key->recirc_id = recirc_id; + } + } else { + /* Out of per CPU action FIFO space. Drop the 'skb' and + * log an error. + */ + ovs_kfree_skb_reason(skb, OVS_DROP_DEFERRED_LIMIT); + + if (net_ratelimit()) { + if (actions) { /* Sample action */ + pr_warn("%s: deferred action limit reached, drop sample action\n", + ovs_dp_name(dp)); + } else { /* Recirc action */ + pr_warn("%s: deferred action limit reached, drop recirc action (recirc_id=%#x)\n", + ovs_dp_name(dp), recirc_id); + } + } + } + return 0; +} + +static void process_deferred_actions(struct datapath *dp) +{ + struct action_fifo *fifo = this_cpu_ptr(action_fifos); + + /* Do not touch the FIFO in case there is no deferred actions. */ + if (action_fifo_is_empty(fifo)) + return; + + /* Finishing executing all deferred actions. */ + do { + struct deferred_action *da = action_fifo_get(fifo); + struct sk_buff *skb = da->skb; + struct sw_flow_key *key = &da->pkt_key; + const struct nlattr *actions = da->actions; + int actions_len = da->actions_len; + + if (actions) + do_execute_actions(dp, skb, key, actions, actions_len); + else + ovs_dp_process_packet(skb, key); + } while (!action_fifo_is_empty(fifo)); + + /* Reset FIFO for the next packet. */ + action_fifo_init(fifo); +} + +/* Execute a list of actions against 'skb'. */ +int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb, + const struct sw_flow_actions *acts, + struct sw_flow_key *key) +{ + int err, level; + + level = __this_cpu_inc_return(exec_actions_level); + if (unlikely(level > OVS_RECURSION_LIMIT)) { + net_crit_ratelimited("ovs: recursion limit reached on datapath %s, probable configuration error\n", + ovs_dp_name(dp)); + ovs_kfree_skb_reason(skb, OVS_DROP_RECURSION_LIMIT); + err = -ENETDOWN; + goto out; + } + + OVS_CB(skb)->acts_origlen = acts->orig_len; + err = do_execute_actions(dp, skb, key, + acts->actions, acts->actions_len); + + if (level == 1) + process_deferred_actions(dp); + +out: + __this_cpu_dec(exec_actions_level); + return err; +} + +int action_fifos_init(void) +{ + action_fifos = alloc_percpu(struct action_fifo); + if (!action_fifos) + return -ENOMEM; + + flow_keys = alloc_percpu(struct action_flow_keys); + if (!flow_keys) { + free_percpu(action_fifos); + return -ENOMEM; + } + + return 0; +} + +void action_fifos_exit(void) +{ + free_percpu(action_fifos); + free_percpu(flow_keys); +} |