X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=datapath%2Factions.c;h=a2a572e3f7df8974c6e3dc486b291d7b5f9d7b6d;hb=e51b8b03f936960d097fc642cb694d119829c054;hp=a037e4320f218adcfbd9f5df29094ed5b6d7d1d0;hpb=34e63086edddcae06d7c1a4fa84fec0861e50758;p=sliver-openvswitch.git diff --git a/datapath/actions.c b/datapath/actions.c index a037e4320..a2a572e3f 100644 --- a/datapath/actions.c +++ b/datapath/actions.c @@ -1,6 +1,6 @@ /* * Distributed under the terms of the GNU GPL version 2. - * Copyright (c) 2007, 2008, 2009 Nicira Networks. + * Copyright (c) 2007, 2008, 2009, 2010, 2011 Nicira Networks. * * Significant portions of this file may be copied from parts of the Linux * kernel, by Linus Torvalds and others. @@ -14,20 +14,32 @@ #include #include #include +#include #include +#include #include #include -#include "datapath.h" -#include "dp_dev.h" + #include "actions.h" +#include "checksum.h" +#include "datapath.h" #include "openvswitch/datapath-protocol.h" +#include "vlan.h" +#include "vport.h" -struct sk_buff * -make_writable(struct sk_buff *skb, gfp_t gfp) +static int do_execute_actions(struct datapath *, struct sk_buff *, + const struct sw_flow_key *, + const struct nlattr *actions, u32 actions_len); + +static struct sk_buff *make_writable(struct sk_buff *skb, unsigned min_headroom) { - if (skb_shared(skb) || skb_cloned(skb)) { - struct sk_buff *nskb = skb_copy(skb, gfp); + if (skb_cloned(skb)) { + struct sk_buff *nskb; + unsigned headroom = max(min_headroom, skb_headroom(skb)); + + nskb = skb_copy_expand(skb, headroom, skb_tailroom(skb), GFP_ATOMIC); if (nskb) { + set_skb_csum_bits(skb, nskb); kfree_skb(skb); return nskb; } @@ -41,19 +53,28 @@ make_writable(struct sk_buff *skb, gfp_t gfp) return NULL; } - -static struct sk_buff * -vlan_pull_tag(struct sk_buff *skb) +static struct sk_buff *strip_vlan(struct sk_buff *skb) { - struct vlan_ethhdr *vh = vlan_eth_hdr(skb); struct ethhdr *eh; + if (vlan_tx_tag_present(skb)) { + vlan_set_tci(skb, 0); + return skb; + } - /* Verify we were given a vlan packet */ - if (vh->h_vlan_proto != htons(ETH_P_8021Q)) + if (unlikely(vlan_eth_hdr(skb)->h_vlan_proto != htons(ETH_P_8021Q) || + skb->len < VLAN_ETH_HLEN)) return skb; - memmove(skb->data + VLAN_HLEN, skb->data, 2 * VLAN_ETH_ALEN); + skb = make_writable(skb, 0); + if (unlikely(!skb)) + return NULL; + + if (get_ip_summed(skb) == OVS_CSUM_COMPLETE) + skb->csum = csum_sub(skb->csum, csum_partial(skb->data + + ETH_HLEN, VLAN_HLEN, 0)); + + memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN); eh = (struct ethhdr *)skb_pull(skb, VLAN_HLEN); @@ -63,362 +84,342 @@ vlan_pull_tag(struct sk_buff *skb) return skb; } - -static struct sk_buff * -modify_vlan_tci(struct datapath *dp, struct sk_buff *skb, - struct odp_flow_key *key, const union odp_action *a, - int n_actions, gfp_t gfp) +static struct sk_buff *modify_vlan_tci(struct sk_buff *skb, __be16 tci) { - u16 tci, mask; + struct vlan_ethhdr *vh; + __be16 old_tci; - if (a->type == ODPAT_SET_VLAN_VID) { - tci = ntohs(a->vlan_vid.vlan_vid); - mask = VLAN_VID_MASK; - key->dl_vlan = htons(tci & mask); - } else { - tci = a->vlan_pcp.vlan_pcp << 13; - mask = VLAN_PCP_MASK; - } + if (vlan_tx_tag_present(skb) || skb->protocol != htons(ETH_P_8021Q)) + return __vlan_hwaccel_put_tag(skb, ntohs(tci)); - skb = make_writable(skb, gfp); - if (!skb) - return ERR_PTR(-ENOMEM); + skb = make_writable(skb, 0); + if (unlikely(!skb)) + return NULL; - if (skb->protocol == htons(ETH_P_8021Q)) { - /* Modify vlan id, but maintain other TCI values */ - struct vlan_ethhdr *vh = vlan_eth_hdr(skb); - vh->h_vlan_TCI = htons((ntohs(vh->h_vlan_TCI) & ~mask) | tci); - } else { - /* Add vlan header */ - - /* Set up checksumming pointers for checksum-deferred packets - * on Xen. Otherwise, dev_queue_xmit() will try to do this - * when we send the packet out on the wire, and it will fail at - * that point because skb_checksum_setup() will not look inside - * an 802.1Q header. */ - skb_checksum_setup(skb); - - /* GSO is not implemented for packets with an 802.1Q header, so - * we have to do segmentation before we add that header. - * - * GSO does work with hardware-accelerated VLAN tagging, but we - * can't use hardware-accelerated VLAN tagging since it - * requires the device to have a VLAN group configured (with - * e.g. vconfig(8)) and we don't do that. - * - * Having to do this here may be a performance loss, since we - * can't take advantage of TSO hardware support, although it - * does not make a measurable network performance difference - * for 1G Ethernet. Fixing that would require patching the - * kernel (either to add GSO support to the VLAN protocol or to - * support hardware-accelerated VLAN tagging without VLAN - * groups configured). */ - if (skb_is_gso(skb)) { - struct sk_buff *segs; - - segs = skb_gso_segment(skb, 0); - kfree_skb(skb); - if (unlikely(IS_ERR(segs))) - return ERR_CAST(segs); - - do { - struct sk_buff *nskb = segs->next; - int err; - - segs->next = NULL; - - segs = __vlan_put_tag(segs, tci); - err = -ENOMEM; - if (segs) { - struct odp_flow_key segkey = *key; - err = execute_actions(dp, segs, - &segkey, a + 1, - n_actions - 1, - gfp); - } - - if (unlikely(err)) { - while ((segs = nskb)) { - nskb = segs->next; - segs->next = NULL; - kfree_skb(segs); - } - return ERR_PTR(err); - } - - segs = nskb; - } while (segs->next); - - skb = segs; - } + if (unlikely(skb->len < VLAN_ETH_HLEN)) + return skb; - /* The hardware-accelerated version of vlan_put_tag() works - * only for a device that has a VLAN group configured (with - * e.g. vconfig(8)), so call the software-only version - * __vlan_put_tag() directly instead. - */ - skb = __vlan_put_tag(skb, tci); - if (!skb) - return ERR_PTR(-ENOMEM); + vh = vlan_eth_hdr(skb); + + old_tci = vh->h_vlan_TCI; + vh->h_vlan_TCI = tci; + + if (get_ip_summed(skb) == OVS_CSUM_COMPLETE) { + __be16 diff[] = { ~old_tci, vh->h_vlan_TCI }; + skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum); } return skb; } -static struct sk_buff *strip_vlan(struct sk_buff *skb, - struct odp_flow_key *key, gfp_t gfp) +static bool is_ip(struct sk_buff *skb, const struct sw_flow_key *key) { - skb = make_writable(skb, gfp); - if (skb) { - vlan_pull_tag(skb); - key->dl_vlan = htons(ODP_VLAN_NONE); - } - return skb; + return (key->dl_type == htons(ETH_P_IP) && + skb->transport_header > skb->network_header); } -static struct sk_buff *set_dl_addr(struct sk_buff *skb, - const struct odp_action_dl_addr *a, - gfp_t gfp) +static __sum16 *get_l4_checksum(struct sk_buff *skb, const struct sw_flow_key *key) { - skb = make_writable(skb, gfp); - if (skb) { - struct ethhdr *eh = eth_hdr(skb); - memcpy(a->type == ODPAT_SET_DL_SRC ? eh->h_source : eh->h_dest, - a->dl_addr, ETH_ALEN); + int transport_len = skb->len - skb_transport_offset(skb); + if (key->nw_proto == IPPROTO_TCP) { + if (likely(transport_len >= sizeof(struct tcphdr))) + return &tcp_hdr(skb)->check; + } else if (key->nw_proto == IPPROTO_UDP) { + if (likely(transport_len >= sizeof(struct udphdr))) + return &udp_hdr(skb)->check; } - return skb; + return NULL; } -/* Updates 'sum', which is a field in 'skb''s data, given that a 4-byte field - * covered by the sum has been changed from 'from' to 'to'. If set, - * 'pseudohdr' indicates that the field is in the TCP or UDP pseudo-header. - * Based on nf_proto_csum_replace4. */ -static void update_csum(__sum16 *sum, struct sk_buff *skb, - __be32 from, __be32 to, int pseudohdr) +static struct sk_buff *set_nw_addr(struct sk_buff *skb, + const struct sw_flow_key *key, + const struct nlattr *a) { - __be32 diff[] = { ~from, to }; - if (skb->ip_summed != CHECKSUM_PARTIAL) { - *sum = csum_fold(csum_partial((char *)diff, sizeof(diff), - ~csum_unfold(*sum))); - if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr) - skb->csum = ~csum_partial((char *)diff, sizeof(diff), - ~skb->csum); - } else if (pseudohdr) - *sum = ~csum_fold(csum_partial((char *)diff, sizeof(diff), - csum_unfold(*sum))); + __be32 new_nwaddr = nla_get_be32(a); + struct iphdr *nh; + __sum16 *check; + __be32 *nwaddr; + + if (unlikely(!is_ip(skb, key))) + return skb; + + skb = make_writable(skb, 0); + if (unlikely(!skb)) + return NULL; + + nh = ip_hdr(skb); + nwaddr = nla_type(a) == ODP_ACTION_ATTR_SET_NW_SRC ? &nh->saddr : &nh->daddr; + + check = get_l4_checksum(skb, key); + if (likely(check)) + inet_proto_csum_replace4(check, skb, *nwaddr, new_nwaddr, 1); + csum_replace4(&nh->check, *nwaddr, new_nwaddr); + + skb_clear_rxhash(skb); + + *nwaddr = new_nwaddr; + + return skb; } -static struct sk_buff *set_nw_addr(struct sk_buff *skb, - struct odp_flow_key *key, - const struct odp_action_nw_addr *a, - gfp_t gfp) +static struct sk_buff *set_nw_tos(struct sk_buff *skb, + const struct sw_flow_key *key, + u8 nw_tos) { - if (key->dl_type != htons(ETH_P_IP)) + if (unlikely(!is_ip(skb, key))) return skb; - skb = make_writable(skb, gfp); + skb = make_writable(skb, 0); if (skb) { struct iphdr *nh = ip_hdr(skb); - u32 *f = a->type == ODPAT_SET_NW_SRC ? &nh->saddr : &nh->daddr; - u32 old = *f; - u32 new = a->nw_addr; - - if (key->nw_proto == IPPROTO_TCP) { - struct tcphdr *th = tcp_hdr(skb); - update_csum(&th->check, skb, old, new, 1); - } else if (key->nw_proto == IPPROTO_UDP) { - struct udphdr *th = udp_hdr(skb); - update_csum(&th->check, skb, old, new, 1); - } - update_csum(&nh->check, skb, old, new, 0); + u8 *f = &nh->tos; + u8 old = *f; + u8 new; + + /* Set the DSCP bits and preserve the ECN bits. */ + new = nw_tos | (nh->tos & INET_ECN_MASK); + csum_replace4(&nh->check, (__force __be32)old, + (__force __be32)new); *f = new; } return skb; } -static struct sk_buff * -set_tp_port(struct sk_buff *skb, struct odp_flow_key *key, - const struct odp_action_tp_port *a, - gfp_t gfp) +static struct sk_buff *set_tp_port(struct sk_buff *skb, + const struct sw_flow_key *key, + const struct nlattr *a) { - int check_ofs; + struct udphdr *th; + __sum16 *check; + __be16 *port; - if (key->dl_type != htons(ETH_P_IP)) + if (unlikely(!is_ip(skb, key))) return skb; - if (key->nw_proto == IPPROTO_TCP) - check_ofs = offsetof(struct tcphdr, check); - else if (key->nw_proto == IPPROTO_UDP) - check_ofs = offsetof(struct udphdr, check); - else + skb = make_writable(skb, 0); + if (unlikely(!skb)) + return NULL; + + /* Must follow make_writable() since that can move the skb data. */ + check = get_l4_checksum(skb, key); + if (unlikely(!check)) return skb; - skb = make_writable(skb, gfp); - if (skb) { - struct udphdr *th = udp_hdr(skb); - u16 *f = a->type == ODPAT_SET_TP_SRC ? &th->source : &th->dest; - u16 old = *f; - u16 new = a->tp_port; - update_csum((u16*)((u8*)skb->data + check_ofs), - skb, old, new, 1); - *f = new; - } - return skb; -} + /* + * Update port and checksum. + * + * This is OK because source and destination port numbers are at the + * same offsets in both UDP and TCP headers, and get_l4_checksum() only + * supports those protocols. + */ + th = udp_hdr(skb); + port = nla_type(a) == ODP_ACTION_ATTR_SET_TP_SRC ? &th->source : &th->dest; + inet_proto_csum_replace2(check, skb, *port, nla_get_be16(a), 0); + *port = nla_get_be16(a); + skb_clear_rxhash(skb); -static inline unsigned packet_length(const struct sk_buff *skb) -{ - unsigned length = skb->len - ETH_HLEN; - if (skb->protocol == htons(ETH_P_8021Q)) - length -= VLAN_HLEN; - return length; + return skb; } -int dp_xmit_skb(struct sk_buff *skb) +/** + * is_spoofed_arp - check for invalid ARP packet + * + * @skb: skbuff containing an Ethernet packet, with network header pointing + * just past the Ethernet and optional 802.1Q header. + * @key: flow key extracted from @skb by flow_extract() + * + * Returns true if @skb is an invalid Ethernet+IPv4 ARP packet: one with screwy + * or truncated header fields or one whose inner and outer Ethernet address + * differ. + */ +static bool is_spoofed_arp(struct sk_buff *skb, const struct sw_flow_key *key) { - struct datapath *dp = skb->dev->br_port->dp; - int len = skb->len; + struct arp_eth_header *arp; - if (packet_length(skb) > skb->dev->mtu && !skb_is_gso(skb)) { - printk(KERN_WARNING "%s: dropped over-mtu packet: %d > %d\n", - dp_name(dp), packet_length(skb), skb->dev->mtu); - kfree_skb(skb); - return -E2BIG; - } + if (key->dl_type != htons(ETH_P_ARP)) + return false; - dev_queue_xmit(skb); + if (skb_network_offset(skb) + sizeof(struct arp_eth_header) > skb->len) + return true; - return len; + arp = (struct arp_eth_header *)skb_network_header(skb); + return (arp->ar_hrd != htons(ARPHRD_ETHER) || + arp->ar_pro != htons(ETH_P_IP) || + arp->ar_hln != ETH_ALEN || + arp->ar_pln != 4 || + compare_ether_addr(arp->ar_sha, eth_hdr(skb)->h_source)); } -static void -do_output(struct datapath *dp, struct sk_buff *skb, int out_port) +static void do_output(struct datapath *dp, struct sk_buff *skb, int out_port) { - struct net_bridge_port *p; - struct net_device *dev; + struct vport *p; if (!skb) goto error; - p = dp->ports[out_port]; + p = rcu_dereference(dp->ports[out_port]); if (!p) goto error; - dev = skb->dev = p->dev; - if (is_dp_dev(dev)) - dp_dev_recv(dev, skb); - else - dp_xmit_skb(skb); + vport_send(p, skb); return; error: kfree_skb(skb); } -/* Never consumes 'skb'. Returns a port that 'skb' should be sent to, -1 if - * none. */ -static int output_group(struct datapath *dp, __u16 group, - struct sk_buff *skb, gfp_t gfp) +static int output_control(struct datapath *dp, struct sk_buff *skb, u64 arg, + const struct sw_flow_key *key) { - struct dp_port_group *g = rcu_dereference(dp->groups[group]); - int prev_port = -1; - int i; - - if (!g) - return -1; - for (i = 0; i < g->n_ports; i++) { - struct net_bridge_port *p = dp->ports[g->ports[i]]; - if (!p || skb->dev == p->dev) - continue; - if (prev_port != -1) { - struct sk_buff *clone = skb_clone(skb, gfp); - if (!clone) - return -1; - do_output(dp, clone, prev_port); - } - prev_port = p->port_no; - } - return prev_port; -} + struct dp_upcall_info upcall; -static int -output_control(struct datapath *dp, struct sk_buff *skb, u32 arg, gfp_t gfp) -{ - skb = skb_clone(skb, gfp); + skb = skb_clone(skb, GFP_ATOMIC); if (!skb) return -ENOMEM; - return dp_output_control(dp, skb, _ODPL_ACTION_NR, arg); + + upcall.cmd = ODP_PACKET_CMD_ACTION; + upcall.key = key; + upcall.userdata = arg; + upcall.sample_pool = 0; + upcall.actions = NULL; + upcall.actions_len = 0; + return dp_upcall(dp, skb, &upcall); } /* Execute a list of actions against 'skb'. */ -int execute_actions(struct datapath *dp, struct sk_buff *skb, - struct odp_flow_key *key, - const union odp_action *a, int n_actions, - gfp_t gfp) +static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, + const struct sw_flow_key *key, + const struct nlattr *actions, u32 actions_len) { /* Every output action needs a separate clone of 'skb', but the common * case is just a single output action, so that doing a clone and * then freeing the original skbuff is wasteful. So the following code * is slightly obscure just to avoid that. */ int prev_port = -1; - int err = 0; - for (; n_actions > 0; a++, n_actions--) { - WARN_ON_ONCE(skb_shared(skb)); + u32 priority = skb->priority; + const struct nlattr *a; + int rem, err; + + for (a = actions, rem = actions_len; rem > 0; a = nla_next(a, &rem)) { if (prev_port != -1) { - do_output(dp, skb_clone(skb, gfp), prev_port); + do_output(dp, skb_clone(skb, GFP_ATOMIC), prev_port); prev_port = -1; } - switch (a->type) { - case ODPAT_OUTPUT: - prev_port = a->output.port; + switch (nla_type(a)) { + case ODP_ACTION_ATTR_OUTPUT: + prev_port = nla_get_u32(a); break; - case ODPAT_OUTPUT_GROUP: - prev_port = output_group(dp, a->output_group.group, - skb, gfp); - break; - - case ODPAT_CONTROLLER: - err = output_control(dp, skb, a->controller.arg, gfp); + case ODP_ACTION_ATTR_CONTROLLER: + err = output_control(dp, skb, nla_get_u64(a), key); if (err) { kfree_skb(skb); return err; } break; - case ODPAT_SET_VLAN_VID: - case ODPAT_SET_VLAN_PCP: - skb = modify_vlan_tci(dp, skb, key, a, n_actions, gfp); - if (IS_ERR(skb)) - return PTR_ERR(skb); + case ODP_ACTION_ATTR_SET_TUNNEL: + OVS_CB(skb)->tun_id = nla_get_be64(a); break; - case ODPAT_STRIP_VLAN: - skb = strip_vlan(skb, key, gfp); + case ODP_ACTION_ATTR_SET_DL_TCI: + skb = modify_vlan_tci(skb, nla_get_be16(a)); break; - case ODPAT_SET_DL_SRC: - case ODPAT_SET_DL_DST: - skb = set_dl_addr(skb, &a->dl_addr, gfp); + case ODP_ACTION_ATTR_STRIP_VLAN: + skb = strip_vlan(skb); break; - case ODPAT_SET_NW_SRC: - case ODPAT_SET_NW_DST: - skb = set_nw_addr(skb, key, &a->nw_addr, gfp); + case ODP_ACTION_ATTR_SET_DL_SRC: + skb = make_writable(skb, 0); + if (!skb) + return -ENOMEM; + memcpy(eth_hdr(skb)->h_source, nla_data(a), ETH_ALEN); break; - case ODPAT_SET_TP_SRC: - case ODPAT_SET_TP_DST: - skb = set_tp_port(skb, key, &a->tp_port, gfp); + case ODP_ACTION_ATTR_SET_DL_DST: + skb = make_writable(skb, 0); + if (!skb) + return -ENOMEM; + memcpy(eth_hdr(skb)->h_dest, nla_data(a), ETH_ALEN); + break; + + case ODP_ACTION_ATTR_SET_NW_SRC: + case ODP_ACTION_ATTR_SET_NW_DST: + skb = set_nw_addr(skb, key, a); + break; + + case ODP_ACTION_ATTR_SET_NW_TOS: + skb = set_nw_tos(skb, key, nla_get_u8(a)); + break; + + case ODP_ACTION_ATTR_SET_TP_SRC: + case ODP_ACTION_ATTR_SET_TP_DST: + skb = set_tp_port(skb, key, a); + break; + + case ODP_ACTION_ATTR_SET_PRIORITY: + skb->priority = nla_get_u32(a); + break; + + case ODP_ACTION_ATTR_POP_PRIORITY: + skb->priority = priority; + break; + + case ODP_ACTION_ATTR_DROP_SPOOFED_ARP: + if (unlikely(is_spoofed_arp(skb, key))) + goto exit; break; } if (!skb) return -ENOMEM; } +exit: if (prev_port != -1) do_output(dp, skb, prev_port); else kfree_skb(skb); - return err; + return 0; +} + +static void sflow_sample(struct datapath *dp, struct sk_buff *skb, + const struct sw_flow_key *key, + const struct nlattr *a, u32 actions_len) +{ + struct sk_buff *nskb; + struct vport *p = OVS_CB(skb)->vport; + struct dp_upcall_info upcall; + + if (unlikely(!p)) + return; + + atomic_inc(&p->sflow_pool); + if (net_random() >= dp->sflow_probability) + return; + + nskb = skb_clone(skb, GFP_ATOMIC); + if (unlikely(!nskb)) + return; + + upcall.cmd = ODP_PACKET_CMD_SAMPLE; + upcall.key = key; + upcall.userdata = 0; + upcall.sample_pool = atomic_read(&p->sflow_pool); + upcall.actions = a; + upcall.actions_len = actions_len; + dp_upcall(dp, nskb, &upcall); +} + +/* Execute a list of actions against 'skb'. */ +int execute_actions(struct datapath *dp, struct sk_buff *skb, + const struct sw_flow_key *key, + const struct nlattr *actions, u32 actions_len) +{ + if (dp->sflow_probability) + sflow_sample(dp, skb, key, actions, actions_len); + + OVS_CB(skb)->tun_id = 0; + + return do_execute_actions(dp, skb, key, actions, actions_len); }