/* * Copyright (c) 2007-2013 Nicira, Inc. * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA */ #include "flow.h" #include "datapath.h" #include <linux/uaccess.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/if_ether.h> #include <linux/if_vlan.h> #include <net/llc_pdu.h> #include <linux/kernel.h> #include <linux/jhash.h> #include <linux/jiffies.h> #include <linux/llc.h> #include <linux/module.h> #include <linux/in.h> #include <linux/rcupdate.h> #include <linux/if_arp.h> #include <linux/ip.h> #include <linux/ipv6.h> #include <linux/sctp.h> #include <linux/smp.h> #include <linux/tcp.h> #include <linux/udp.h> #include <linux/icmp.h> #include <linux/icmpv6.h> #include <linux/rculist.h> #include <net/ip.h> #include <net/ip_tunnels.h> #include <net/ipv6.h> #include <net/ndisc.h> u64 ovs_flow_used_time(unsigned long flow_jiffies) { struct timespec cur_ts; u64 cur_ms, idle_ms; ktime_get_ts(&cur_ts); idle_ms = jiffies_to_msecs(jiffies - flow_jiffies); cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC + cur_ts.tv_nsec / NSEC_PER_MSEC; return cur_ms - idle_ms; } #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF)) void ovs_flow_stats_update(struct sw_flow *flow, struct sk_buff *skb) { struct flow_stats *stats; __be16 tcp_flags = 0; if (!flow->stats.is_percpu) stats = flow->stats.stat; else stats = this_cpu_ptr(flow->stats.cpu_stats); if ((flow->key.eth.type == htons(ETH_P_IP) || flow->key.eth.type == htons(ETH_P_IPV6)) && flow->key.ip.proto == IPPROTO_TCP && likely(skb->len >= skb_transport_offset(skb) + sizeof(struct tcphdr))) { tcp_flags = TCP_FLAGS_BE16(tcp_hdr(skb)); } spin_lock(&stats->lock); stats->used = jiffies; stats->packet_count++; stats->byte_count += skb->len; stats->tcp_flags |= tcp_flags; spin_unlock(&stats->lock); } static void stats_read(struct flow_stats *stats, struct ovs_flow_stats *ovs_stats, unsigned long *used, __be16 *tcp_flags) { spin_lock(&stats->lock); if (time_after(stats->used, *used)) *used = stats->used; *tcp_flags |= stats->tcp_flags; ovs_stats->n_packets += stats->packet_count; ovs_stats->n_bytes += stats->byte_count; spin_unlock(&stats->lock); } void ovs_flow_stats_get(struct sw_flow *flow, struct ovs_flow_stats *ovs_stats, unsigned long *used, __be16 *tcp_flags) { int cpu, cur_cpu; *used = 0; *tcp_flags = 0; memset(ovs_stats, 0, sizeof(*ovs_stats)); if (!flow->stats.is_percpu) { stats_read(flow->stats.stat, ovs_stats, used, tcp_flags); } else { cur_cpu = get_cpu(); for_each_possible_cpu(cpu) { struct flow_stats *stats; if (cpu == cur_cpu) local_bh_disable(); stats = per_cpu_ptr(flow->stats.cpu_stats, cpu); stats_read(stats, ovs_stats, used, tcp_flags); if (cpu == cur_cpu) local_bh_enable(); } put_cpu(); } } static void stats_reset(struct flow_stats *stats) { spin_lock(&stats->lock); stats->used = 0; stats->packet_count = 0; stats->byte_count = 0; stats->tcp_flags = 0; spin_unlock(&stats->lock); } void ovs_flow_stats_clear(struct sw_flow *flow) { int cpu, cur_cpu; if (!flow->stats.is_percpu) { stats_reset(flow->stats.stat); } else { cur_cpu = get_cpu(); for_each_possible_cpu(cpu) { if (cpu == cur_cpu) local_bh_disable(); stats_reset(per_cpu_ptr(flow->stats.cpu_stats, cpu)); if (cpu == cur_cpu) local_bh_enable(); } put_cpu(); } } static int check_header(struct sk_buff *skb, int len) { if (unlikely(skb->len < len)) return -EINVAL; if (unlikely(!pskb_may_pull(skb, len))) return -ENOMEM; return 0; } static bool arphdr_ok(struct sk_buff *skb) { return pskb_may_pull(skb, skb_network_offset(skb) + sizeof(struct arp_eth_header)); } static int check_iphdr(struct sk_buff *skb) { unsigned int nh_ofs = skb_network_offset(skb); unsigned int ip_len; int err; err = check_header(skb, nh_ofs + sizeof(struct iphdr)); if (unlikely(err)) return err; ip_len = ip_hdrlen(skb); if (unlikely(ip_len < sizeof(struct iphdr) || skb->len < nh_ofs + ip_len)) return -EINVAL; skb_set_transport_header(skb, nh_ofs + ip_len); return 0; } static bool tcphdr_ok(struct sk_buff *skb) { int th_ofs = skb_transport_offset(skb); int tcp_len; if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr)))) return false; tcp_len = tcp_hdrlen(skb); if (unlikely(tcp_len < sizeof(struct tcphdr) || skb->len < th_ofs + tcp_len)) return false; return true; } static bool udphdr_ok(struct sk_buff *skb) { return pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct udphdr)); } static bool sctphdr_ok(struct sk_buff *skb) { return pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct sctphdr)); } static bool icmphdr_ok(struct sk_buff *skb) { return pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct icmphdr)); } static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key) { unsigned int nh_ofs = skb_network_offset(skb); unsigned int nh_len; int payload_ofs; struct ipv6hdr *nh; uint8_t nexthdr; __be16 frag_off; int err; err = check_header(skb, nh_ofs + sizeof(*nh)); if (unlikely(err)) return err; nh = ipv6_hdr(skb); nexthdr = nh->nexthdr; payload_ofs = (u8 *)(nh + 1) - skb->data; key->ip.proto = NEXTHDR_NONE; key->ip.tos = ipv6_get_dsfield(nh); key->ip.ttl = nh->hop_limit; key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL); key->ipv6.addr.src = nh->saddr; key->ipv6.addr.dst = nh->daddr; payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off); if (unlikely(payload_ofs < 0)) return -EINVAL; if (frag_off) { if (frag_off & htons(~0x7)) key->ip.frag = OVS_FRAG_TYPE_LATER; else key->ip.frag = OVS_FRAG_TYPE_FIRST; } nh_len = payload_ofs - nh_ofs; skb_set_transport_header(skb, nh_ofs + nh_len); key->ip.proto = nexthdr; return nh_len; } static bool icmp6hdr_ok(struct sk_buff *skb) { return pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct icmp6hdr)); } static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key) { struct qtag_prefix { __be16 eth_type; /* ETH_P_8021Q */ __be16 tci; }; struct qtag_prefix *qp; if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16))) return 0; if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) + sizeof(__be16)))) return -ENOMEM; qp = (struct qtag_prefix *) skb->data; key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT); __skb_pull(skb, sizeof(struct qtag_prefix)); return 0; } static __be16 parse_ethertype(struct sk_buff *skb) { struct llc_snap_hdr { u8 dsap; /* Always 0xAA */ u8 ssap; /* Always 0xAA */ u8 ctrl; u8 oui[3]; __be16 ethertype; }; struct llc_snap_hdr *llc; __be16 proto; proto = *(__be16 *) skb->data; __skb_pull(skb, sizeof(__be16)); if (ntohs(proto) >= ETH_P_802_3_MIN) return proto; if (skb->len < sizeof(struct llc_snap_hdr)) return htons(ETH_P_802_2); if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr)))) return htons(0); llc = (struct llc_snap_hdr *) skb->data; if (llc->dsap != LLC_SAP_SNAP || llc->ssap != LLC_SAP_SNAP || (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0) return htons(ETH_P_802_2); __skb_pull(skb, sizeof(struct llc_snap_hdr)); if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN) return llc->ethertype; return htons(ETH_P_802_2); } static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key, int nh_len) { struct icmp6hdr *icmp = icmp6_hdr(skb); /* The ICMPv6 type and code fields use the 16-bit transport port * fields, so we need to store them in 16-bit network byte order. */ key->ipv6.tp.src = htons(icmp->icmp6_type); key->ipv6.tp.dst = htons(icmp->icmp6_code); if (icmp->icmp6_code == 0 && (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION || icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) { int icmp_len = skb->len - skb_transport_offset(skb); struct nd_msg *nd; int offset; /* In order to process neighbor discovery options, we need the * entire packet. */ if (unlikely(icmp_len < sizeof(*nd))) return 0; if (unlikely(skb_linearize(skb))) return -ENOMEM; nd = (struct nd_msg *)skb_transport_header(skb); key->ipv6.nd.target = nd->target; icmp_len -= sizeof(*nd); offset = 0; while (icmp_len >= 8) { struct nd_opt_hdr *nd_opt = (struct nd_opt_hdr *)(nd->opt + offset); int opt_len = nd_opt->nd_opt_len * 8; if (unlikely(!opt_len || opt_len > icmp_len)) return 0; /* Store the link layer address if the appropriate * option is provided. It is considered an error if * the same link layer option is specified twice. */ if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR && opt_len == 8) { if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll))) goto invalid; memcpy(key->ipv6.nd.sll, &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN); } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR && opt_len == 8) { if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll))) goto invalid; memcpy(key->ipv6.nd.tll, &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN); } icmp_len -= opt_len; offset += opt_len; } } return 0; invalid: memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target)); memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll)); memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll)); return 0; } /** * ovs_flow_extract - extracts a flow key from an Ethernet frame. * @skb: sk_buff that contains the frame, with skb->data pointing to the * Ethernet header * @in_port: port number on which @skb was received. * @key: output flow key * * The caller must ensure that skb->len >= ETH_HLEN. * * Returns 0 if successful, otherwise a negative errno value. * * Initializes @skb header pointers as follows: * * - skb->mac_header: the Ethernet header. * * - skb->network_header: just past the Ethernet header, or just past the * VLAN header, to the first byte of the Ethernet payload. * * - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6 * on output, then just past the IP header, if one is present and * of a correct length, otherwise the same as skb->network_header. * For other key->eth.type values it is left untouched. */ int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key) { int error; struct ethhdr *eth; memset(key, 0, sizeof(*key)); key->phy.priority = skb->priority; if (OVS_CB(skb)->tun_key) memcpy(&key->tun_key, OVS_CB(skb)->tun_key, sizeof(key->tun_key)); key->phy.in_port = in_port; key->phy.skb_mark = skb->mark; skb_reset_mac_header(skb); /* Link layer. We are guaranteed to have at least the 14 byte Ethernet * header in the linear data area. */ eth = eth_hdr(skb); memcpy(key->eth.src, eth->h_source, ETH_ALEN); memcpy(key->eth.dst, eth->h_dest, ETH_ALEN); __skb_pull(skb, 2 * ETH_ALEN); /* We are going to push all headers that we pull, so no need to * update skb->csum here. */ if (vlan_tx_tag_present(skb)) key->eth.tci = htons(skb->vlan_tci); else if (eth->h_proto == htons(ETH_P_8021Q)) if (unlikely(parse_vlan(skb, key))) return -ENOMEM; key->eth.type = parse_ethertype(skb); if (unlikely(key->eth.type == htons(0))) return -ENOMEM; skb_reset_network_header(skb); __skb_push(skb, skb->data - skb_mac_header(skb)); /* Network layer. */ if (key->eth.type == htons(ETH_P_IP)) { struct iphdr *nh; __be16 offset; error = check_iphdr(skb); if (unlikely(error)) { if (error == -EINVAL) { skb->transport_header = skb->network_header; error = 0; } return error; } nh = ip_hdr(skb); key->ipv4.addr.src = nh->saddr; key->ipv4.addr.dst = nh->daddr; key->ip.proto = nh->protocol; key->ip.tos = nh->tos; key->ip.ttl = nh->ttl; offset = nh->frag_off & htons(IP_OFFSET); if (offset) { key->ip.frag = OVS_FRAG_TYPE_LATER; return 0; } if (nh->frag_off & htons(IP_MF) || skb_shinfo(skb)->gso_type & SKB_GSO_UDP) key->ip.frag = OVS_FRAG_TYPE_FIRST; /* Transport layer. */ if (key->ip.proto == IPPROTO_TCP) { if (tcphdr_ok(skb)) { struct tcphdr *tcp = tcp_hdr(skb); key->ipv4.tp.src = tcp->source; key->ipv4.tp.dst = tcp->dest; key->ipv4.tp.flags = TCP_FLAGS_BE16(tcp); } } else if (key->ip.proto == IPPROTO_UDP) { if (udphdr_ok(skb)) { struct udphdr *udp = udp_hdr(skb); key->ipv4.tp.src = udp->source; key->ipv4.tp.dst = udp->dest; } } else if (key->ip.proto == IPPROTO_SCTP) { if (sctphdr_ok(skb)) { struct sctphdr *sctp = sctp_hdr(skb); key->ipv4.tp.src = sctp->source; key->ipv4.tp.dst = sctp->dest; } } else if (key->ip.proto == IPPROTO_ICMP) { if (icmphdr_ok(skb)) { struct icmphdr *icmp = icmp_hdr(skb); /* The ICMP type and code fields use the 16-bit * transport port fields, so we need to store * them in 16-bit network byte order. */ key->ipv4.tp.src = htons(icmp->type); key->ipv4.tp.dst = htons(icmp->code); } } } else if ((key->eth.type == htons(ETH_P_ARP) || key->eth.type == htons(ETH_P_RARP)) && arphdr_ok(skb)) { struct arp_eth_header *arp; arp = (struct arp_eth_header *)skb_network_header(skb); if (arp->ar_hrd == htons(ARPHRD_ETHER) && arp->ar_pro == htons(ETH_P_IP) && arp->ar_hln == ETH_ALEN && arp->ar_pln == 4) { /* We only match on the lower 8 bits of the opcode. */ if (ntohs(arp->ar_op) <= 0xff) key->ip.proto = ntohs(arp->ar_op); memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src)); memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst)); memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN); memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN); } } else if (key->eth.type == htons(ETH_P_IPV6)) { int nh_len; /* IPv6 Header + Extensions */ nh_len = parse_ipv6hdr(skb, key); if (unlikely(nh_len < 0)) { if (nh_len == -EINVAL) { skb->transport_header = skb->network_header; error = 0; } else { error = nh_len; } return error; } if (key->ip.frag == OVS_FRAG_TYPE_LATER) return 0; if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP) key->ip.frag = OVS_FRAG_TYPE_FIRST; /* Transport layer. */ if (key->ip.proto == NEXTHDR_TCP) { if (tcphdr_ok(skb)) { struct tcphdr *tcp = tcp_hdr(skb); key->ipv6.tp.src = tcp->source; key->ipv6.tp.dst = tcp->dest; key->ipv6.tp.flags = TCP_FLAGS_BE16(tcp); } } else if (key->ip.proto == NEXTHDR_UDP) { if (udphdr_ok(skb)) { struct udphdr *udp = udp_hdr(skb); key->ipv6.tp.src = udp->source; key->ipv6.tp.dst = udp->dest; } } else if (key->ip.proto == NEXTHDR_SCTP) { if (sctphdr_ok(skb)) { struct sctphdr *sctp = sctp_hdr(skb); key->ipv6.tp.src = sctp->source; key->ipv6.tp.dst = sctp->dest; } } else if (key->ip.proto == NEXTHDR_ICMP) { if (icmp6hdr_ok(skb)) { error = parse_icmpv6(skb, key, nh_len); if (error) return error; } } } return 0; }