diff options
Diffstat (limited to 'net/openvswitch/datapath.c')
| -rw-r--r-- | net/openvswitch/datapath.c | 1912 |
1 files changed, 1912 insertions, 0 deletions
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c new file mode 100644 index 00000000000..9a2725114e9 --- /dev/null +++ b/net/openvswitch/datapath.c @@ -0,0 +1,1912 @@ +/* + * Copyright (c) 2007-2011 Nicira Networks. + * + * 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 + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/if_arp.h> +#include <linux/if_vlan.h> +#include <linux/in.h> +#include <linux/ip.h> +#include <linux/jhash.h> +#include <linux/delay.h> +#include <linux/time.h> +#include <linux/etherdevice.h> +#include <linux/genetlink.h> +#include <linux/kernel.h> +#include <linux/kthread.h> +#include <linux/mutex.h> +#include <linux/percpu.h> +#include <linux/rcupdate.h> +#include <linux/tcp.h> +#include <linux/udp.h> +#include <linux/version.h> +#include <linux/ethtool.h> +#include <linux/wait.h> +#include <asm/system.h> +#include <asm/div64.h> +#include <linux/highmem.h> +#include <linux/netfilter_bridge.h> +#include <linux/netfilter_ipv4.h> +#include <linux/inetdevice.h> +#include <linux/list.h> +#include <linux/openvswitch.h> +#include <linux/rculist.h> +#include <linux/dmi.h> +#include <linux/workqueue.h> +#include <net/genetlink.h> + +#include "datapath.h" +#include "flow.h" +#include "vport-internal_dev.h" + +/** + * DOC: Locking: + * + * Writes to device state (add/remove datapath, port, set operations on vports, + * etc.) are protected by RTNL. + * + * Writes to other state (flow table modifications, set miscellaneous datapath + * parameters, etc.) are protected by genl_mutex. The RTNL lock nests inside + * genl_mutex. + * + * Reads are protected by RCU. + * + * There are a few special cases (mostly stats) that have their own + * synchronization but they nest under all of above and don't interact with + * each other. + */ + +/* Global list of datapaths to enable dumping them all out. + * Protected by genl_mutex. + */ +static LIST_HEAD(dps); + +#define REHASH_FLOW_INTERVAL (10 * 60 * HZ) +static void rehash_flow_table(struct work_struct *work); +static DECLARE_DELAYED_WORK(rehash_flow_wq, rehash_flow_table); + +static struct vport *new_vport(const struct vport_parms *); +static int queue_gso_packets(int dp_ifindex, struct sk_buff *, + const struct dp_upcall_info *); +static int queue_userspace_packet(int dp_ifindex, struct sk_buff *, + const struct dp_upcall_info *); + +/* Must be called with rcu_read_lock, genl_mutex, or RTNL lock. */ +static struct datapath *get_dp(int dp_ifindex) +{ + struct datapath *dp = NULL; + struct net_device *dev; + + rcu_read_lock(); + dev = dev_get_by_index_rcu(&init_net, dp_ifindex); + if (dev) { + struct vport *vport = ovs_internal_dev_get_vport(dev); + if (vport) + dp = vport->dp; + } + rcu_read_unlock(); + + return dp; +} + +/* Must be called with rcu_read_lock or RTNL lock. */ +const char *ovs_dp_name(const struct datapath *dp) +{ + struct vport *vport = rcu_dereference_rtnl(dp->ports[OVSP_LOCAL]); + return vport->ops->get_name(vport); +} + +static int get_dpifindex(struct datapath *dp) +{ + struct vport *local; + int ifindex; + + rcu_read_lock(); + + local = rcu_dereference(dp->ports[OVSP_LOCAL]); + if (local) + ifindex = local->ops->get_ifindex(local); + else + ifindex = 0; + + rcu_read_unlock(); + + return ifindex; +} + +static void destroy_dp_rcu(struct rcu_head *rcu) +{ + struct datapath *dp = container_of(rcu, struct datapath, rcu); + + ovs_flow_tbl_destroy((__force struct flow_table *)dp->table); + free_percpu(dp->stats_percpu); + kfree(dp); +} + +/* Called with RTNL lock and genl_lock. */ +static struct vport *new_vport(const struct vport_parms *parms) +{ + struct vport *vport; + + vport = ovs_vport_add(parms); + if (!IS_ERR(vport)) { + struct datapath *dp = parms->dp; + + rcu_assign_pointer(dp->ports[parms->port_no], vport); + list_add(&vport->node, &dp->port_list); + } + + return vport; +} + +/* Called with RTNL lock. */ +void ovs_dp_detach_port(struct vport *p) +{ + ASSERT_RTNL(); + + /* First drop references to device. */ + list_del(&p->node); + rcu_assign_pointer(p->dp->ports[p->port_no], NULL); + + /* Then destroy it. */ + ovs_vport_del(p); +} + +/* Must be called with rcu_read_lock. */ +void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb) +{ + struct datapath *dp = p->dp; + struct sw_flow *flow; + struct dp_stats_percpu *stats; + struct sw_flow_key key; + u64 *stats_counter; + int error; + int key_len; + + stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id()); + + /* Extract flow from 'skb' into 'key'. */ + error = ovs_flow_extract(skb, p->port_no, &key, &key_len); + if (unlikely(error)) { + kfree_skb(skb); + return; + } + + /* Look up flow. */ + flow = ovs_flow_tbl_lookup(rcu_dereference(dp->table), &key, key_len); + if (unlikely(!flow)) { + struct dp_upcall_info upcall; + + upcall.cmd = OVS_PACKET_CMD_MISS; + upcall.key = &key; + upcall.userdata = NULL; + upcall.pid = p->upcall_pid; + ovs_dp_upcall(dp, skb, &upcall); + consume_skb(skb); + stats_counter = &stats->n_missed; + goto out; + } + + OVS_CB(skb)->flow = flow; + + stats_counter = &stats->n_hit; + ovs_flow_used(OVS_CB(skb)->flow, skb); + ovs_execute_actions(dp, skb); + +out: + /* Update datapath statistics. */ + u64_stats_update_begin(&stats->sync); + (*stats_counter)++; + u64_stats_update_end(&stats->sync); +} + +static struct genl_family dp_packet_genl_family = { + .id = GENL_ID_GENERATE, + .hdrsize = sizeof(struct ovs_header), + .name = OVS_PACKET_FAMILY, + .version = OVS_PACKET_VERSION, + .maxattr = OVS_PACKET_ATTR_MAX +}; + +int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb, + const struct dp_upcall_info *upcall_info) +{ + struct dp_stats_percpu *stats; + int dp_ifindex; + int err; + + if (upcall_info->pid == 0) { + err = -ENOTCONN; + goto err; + } + + dp_ifindex = get_dpifindex(dp); + if (!dp_ifindex) { + err = -ENODEV; + goto err; + } + + if (!skb_is_gso(skb)) + err = queue_userspace_packet(dp_ifindex, skb, upcall_info); + else + err = queue_gso_packets(dp_ifindex, skb, upcall_info); + if (err) + goto err; + + return 0; + +err: + stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id()); + + u64_stats_update_begin(&stats->sync); + stats->n_lost++; + u64_stats_update_end(&stats->sync); + + return err; +} + +static int queue_gso_packets(int dp_ifindex, struct sk_buff *skb, + const struct dp_upcall_info *upcall_info) +{ + struct dp_upcall_info later_info; + struct sw_flow_key later_key; + struct sk_buff *segs, *nskb; + int err; + + segs = skb_gso_segment(skb, NETIF_F_SG | NETIF_F_HW_CSUM); + if (IS_ERR(skb)) + return PTR_ERR(skb); + + /* Queue all of the segments. */ + skb = segs; + do { + err = queue_userspace_packet(dp_ifindex, skb, upcall_info); + if (err) + break; + + if (skb == segs && skb_shinfo(skb)->gso_type & SKB_GSO_UDP) { + /* The initial flow key extracted by ovs_flow_extract() + * in this case is for a first fragment, so we need to + * properly mark later fragments. + */ + later_key = *upcall_info->key; + later_key.ip.frag = OVS_FRAG_TYPE_LATER; + + later_info = *upcall_info; + later_info.key = &later_key; + upcall_info = &later_info; + } + } while ((skb = skb->next)); + + /* Free all of the segments. */ + skb = segs; + do { + nskb = skb->next; + if (err) + kfree_skb(skb); + else + consume_skb(skb); + } while ((skb = nskb)); + return err; +} + +static int queue_userspace_packet(int dp_ifindex, struct sk_buff *skb, + const struct dp_upcall_info *upcall_info) +{ + struct ovs_header *upcall; + struct sk_buff *nskb = NULL; + struct sk_buff *user_skb; /* to be queued to userspace */ + struct nlattr *nla; + unsigned int len; + int err; + + if (vlan_tx_tag_present(skb)) { + nskb = skb_clone(skb, GFP_ATOMIC); + if (!nskb) + return -ENOMEM; + + nskb = __vlan_put_tag(nskb, vlan_tx_tag_get(nskb)); + if (!skb) + return -ENOMEM; + + nskb->vlan_tci = 0; + skb = nskb; + } + + if (nla_attr_size(skb->len) > USHRT_MAX) { + err = -EFBIG; + goto out; + } + + len = sizeof(struct ovs_header); + len += nla_total_size(skb->len); + len += nla_total_size(FLOW_BUFSIZE); + if (upcall_info->cmd == OVS_PACKET_CMD_ACTION) + len += nla_total_size(8); + + user_skb = genlmsg_new(len, GFP_ATOMIC); + if (!user_skb) { + err = -ENOMEM; + goto out; + } + + upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family, + 0, upcall_info->cmd); + upcall->dp_ifindex = dp_ifindex; + + nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_KEY); + ovs_flow_to_nlattrs(upcall_info->key, user_skb); + nla_nest_end(user_skb, nla); + + if (upcall_info->userdata) + nla_put_u64(user_skb, OVS_PACKET_ATTR_USERDATA, + nla_get_u64(upcall_info->userdata)); + + nla = __nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, skb->len); + + skb_copy_and_csum_dev(skb, nla_data(nla)); + + err = genlmsg_unicast(&init_net, user_skb, upcall_info->pid); + +out: + kfree_skb(nskb); + return err; +} + +/* Called with genl_mutex. */ +static int flush_flows(int dp_ifindex) +{ + struct flow_table *old_table; + struct flow_table *new_table; + struct datapath *dp; + + dp = get_dp(dp_ifindex); + if (!dp) + return -ENODEV; + + old_table = genl_dereference(dp->table); + new_table = ovs_flow_tbl_alloc(TBL_MIN_BUCKETS); + if (!new_table) + return -ENOMEM; + + rcu_assign_pointer(dp->table, new_table); + + ovs_flow_tbl_deferred_destroy(old_table); + return 0; +} + +static int validate_actions(const struct nlattr *attr, + const struct sw_flow_key *key, int depth); + +static int validate_sample(const struct nlattr *attr, + const struct sw_flow_key *key, int depth) +{ + const struct nlattr *attrs[OVS_SAMPLE_ATTR_MAX + 1]; + const struct nlattr *probability, *actions; + const struct nlattr *a; + int rem; + + memset(attrs, 0, sizeof(attrs)); + nla_for_each_nested(a, attr, rem) { + int type = nla_type(a); + if (!type || type > OVS_SAMPLE_ATTR_MAX || attrs[type]) + return -EINVAL; + attrs[type] = a; + } + if (rem) + return -EINVAL; + + probability = attrs[OVS_SAMPLE_ATTR_PROBABILITY]; + if (!probability || nla_len(probability) != sizeof(u32)) + return -EINVAL; + + actions = attrs[OVS_SAMPLE_ATTR_ACTIONS]; + if (!actions || (nla_len(actions) && nla_len(actions) < NLA_HDRLEN)) + return -EINVAL; + return validate_actions(actions, key, depth + 1); +} + +static int validate_set(const struct nlattr *a, + const struct sw_flow_key *flow_key) +{ + const struct nlattr *ovs_key = nla_data(a); + int key_type = nla_type(ovs_key); + + /* There can be only one key in a action */ + if (nla_total_size(nla_len(ovs_key)) != nla_len(a)) + return -EINVAL; + + if (key_type > OVS_KEY_ATTR_MAX || + nla_len(ovs_key) != ovs_key_lens[key_type]) + return -EINVAL; + + switch (key_type) { + const struct ovs_key_ipv4 *ipv4_key; + + case OVS_KEY_ATTR_PRIORITY: + case OVS_KEY_ATTR_ETHERNET: + break; + + case OVS_KEY_ATTR_IPV4: + if (flow_key->eth.type != htons(ETH_P_IP)) + return -EINVAL; + + if (!flow_key->ipv4.addr.src || !flow_key->ipv4.addr.dst) + return -EINVAL; + + ipv4_key = nla_data(ovs_key); + if (ipv4_key->ipv4_proto != flow_key->ip.proto) + return -EINVAL; + + if (ipv4_key->ipv4_frag != flow_key->ip.frag) + return -EINVAL; + + break; + + case OVS_KEY_ATTR_TCP: + if (flow_key->ip.proto != IPPROTO_TCP) + return -EINVAL; + + if (!flow_key->ipv4.tp.src || !flow_key->ipv4.tp.dst) + return -EINVAL; + + break; + + case OVS_KEY_ATTR_UDP: + if (flow_key->ip.proto != IPPROTO_UDP) + return -EINVAL; + + if (!flow_key->ipv4.tp.src || !flow_key->ipv4.tp.dst) + return -EINVAL; + break; + + default: + return -EINVAL; + } + + return 0; +} + +static int validate_userspace(const struct nlattr *attr) +{ + static const struct nla_policy userspace_policy[OVS_USERSPACE_ATTR_MAX + 1] = { + [OVS_USERSPACE_ATTR_PID] = {.type = NLA_U32 }, + [OVS_USERSPACE_ATTR_USERDATA] = {.type = NLA_U64 }, + }; + struct nlattr *a[OVS_USERSPACE_ATTR_MAX + 1]; + int error; + + error = nla_parse_nested(a, OVS_USERSPACE_ATTR_MAX, + attr, userspace_policy); + if (error) + return error; + + if (!a[OVS_USERSPACE_ATTR_PID] || + !nla_get_u32(a[OVS_USERSPACE_ATTR_PID])) + return -EINVAL; + + return 0; +} + +static int validate_actions(const struct nlattr *attr, + const struct sw_flow_key *key, int depth) +{ + const struct nlattr *a; + int rem, err; + + if (depth >= SAMPLE_ACTION_DEPTH) + return -EOVERFLOW; + + nla_for_each_nested(a, attr, rem) { + /* Expected argument lengths, (u32)-1 for variable length. */ + static const u32 action_lens[OVS_ACTION_ATTR_MAX + 1] = { + [OVS_ACTION_ATTR_OUTPUT] = sizeof(u32), + [OVS_ACTION_ATTR_USERSPACE] = (u32)-1, + [OVS_ACTION_ATTR_PUSH_VLAN] = sizeof(struct ovs_action_push_vlan), + [OVS_ACTION_ATTR_POP_VLAN] = 0, + [OVS_ACTION_ATTR_SET] = (u32)-1, + [OVS_ACTION_ATTR_SAMPLE] = (u32)-1 + }; + const struct ovs_action_push_vlan *vlan; + int type = nla_type(a); + + if (type > OVS_ACTION_ATTR_MAX || + (action_lens[type] != nla_len(a) && + action_lens[type] != (u32)-1)) + return -EINVAL; + + switch (type) { + case OVS_ACTION_ATTR_UNSPEC: + return -EINVAL; + + case OVS_ACTION_ATTR_USERSPACE: + err = validate_userspace(a); + if (err) + return err; + break; + + case OVS_ACTION_ATTR_OUTPUT: + if (nla_get_u32(a) >= DP_MAX_PORTS) + return -EINVAL; + break; + + + case OVS_ACTION_ATTR_POP_VLAN: + break; + + case OVS_ACTION_ATTR_PUSH_VLAN: + vlan = nla_data(a); + if (vlan->vlan_tpid != htons(ETH_P_8021Q)) + return -EINVAL; + if (!(vlan->vlan_tci & htons(VLAN_TAG_PRESENT))) + return -EINVAL; + break; + + case OVS_ACTION_ATTR_SET: + err = validate_set(a, key); + if (err) + return err; + break; + + case OVS_ACTION_ATTR_SAMPLE: + err = validate_sample(a, key, depth); + if (err) + return err; + break; + + default: + return -EINVAL; + } + } + + if (rem > 0) + return -EINVAL; + + return 0; +} + +static void clear_stats(struct sw_flow *flow) +{ + flow->used = 0; + flow->tcp_flags = 0; + flow->packet_count = 0; + flow->byte_count = 0; +} + +static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) +{ + struct ovs_header *ovs_header = info->userhdr; + struct nlattr **a = info->attrs; + struct sw_flow_actions *acts; + struct sk_buff *packet; + struct sw_flow *flow; + struct datapath *dp; + struct ethhdr *eth; + int len; + int err; + int key_len; + + err = -EINVAL; + if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] || + !a[OVS_PACKET_ATTR_ACTIONS] || + nla_len(a[OVS_PACKET_ATTR_PACKET]) < ETH_HLEN) + goto err; + + len = nla_len(a[OVS_PACKET_ATTR_PACKET]); + packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL); + err = -ENOMEM; + if (!packet) + goto err; + skb_reserve(packet, NET_IP_ALIGN); + + memcpy(__skb_put(packet, len), nla_data(a[OVS_PACKET_ATTR_PACKET]), len); + + skb_reset_mac_header(packet); + eth = eth_hdr(packet); + + /* Normally, setting the skb 'protocol' field would be handled by a + * call to eth_type_trans(), but it assumes there's a sending + * device, which we may not have. */ + if (ntohs(eth->h_proto) >= 1536) + packet->protocol = eth->h_proto; + else + packet->protocol = htons(ETH_P_802_2); + + /* Build an sw_flow for sending this packet. */ + flow = ovs_flow_alloc(); + err = PTR_ERR(flow); + if (IS_ERR(flow)) + goto err_kfree_skb; + + err = ovs_flow_extract(packet, -1, &flow->key, &key_len); + if (err) + goto err_flow_free; + + err = ovs_flow_metadata_from_nlattrs(&flow->key.phy.priority, + &flow->key.phy.in_port, + a[OVS_PACKET_ATTR_KEY]); + if (err) + goto err_flow_free; + + err = validate_actions(a[OVS_PACKET_ATTR_ACTIONS], &flow->key, 0); + if (err) + goto err_flow_free; + + flow->hash = ovs_flow_hash(&flow->key, key_len); + + acts = ovs_flow_actions_alloc(a[OVS_PACKET_ATTR_ACTIONS]); + err = PTR_ERR(acts); + if (IS_ERR(acts)) + goto err_flow_free; + rcu_assign_pointer(flow->sf_acts, acts); + + OVS_CB(packet)->flow = flow; + packet->priority = flow->key.phy.priority; + + rcu_read_lock(); + dp = get_dp(ovs_header->dp_ifindex); + err = -ENODEV; + if (!dp) + goto err_unlock; + + local_bh_disable(); + err = ovs_execute_actions(dp, packet); + local_bh_enable(); + rcu_read_unlock(); + + ovs_flow_free(flow); + return err; + +err_unlock: + rcu_read_unlock(); +err_flow_free: + ovs_flow_free(flow); +err_kfree_skb: + kfree_skb(packet); +err: + return err; +} + +static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = { + [OVS_PACKET_ATTR_PACKET] = { .type = NLA_UNSPEC }, + [OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED }, + [OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED }, +}; + +static struct genl_ops dp_packet_genl_ops[] = { + { .cmd = OVS_PACKET_CMD_EXECUTE, + .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */ + .policy = packet_policy, + .doit = ovs_packet_cmd_execute + } +}; + +static void get_dp_stats(struct datapath *dp, struct ovs_dp_stats *stats) +{ + int i; + struct flow_table *table = genl_dereference(dp->table); + + stats->n_flows = ovs_flow_tbl_count(table); + + stats->n_hit = stats->n_missed = stats->n_lost = 0; + for_each_possible_cpu(i) { + const struct dp_stats_percpu *percpu_stats; + struct dp_stats_percpu local_stats; + unsigned int start; + + percpu_stats = per_cpu_ptr(dp->stats_percpu, i); + + do { + start = u64_stats_fetch_begin_bh(&percpu_stats->sync); + local_stats = *percpu_stats; + } while (u64_stats_fetch_retry_bh(&percpu_stats->sync, start)); + + stats->n_hit += local_stats.n_hit; + stats->n_missed += local_stats.n_missed; + stats->n_lost += local_stats.n_lost; + } +} + +static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = { + [OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED }, + [OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED }, + [OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG }, +}; + +static struct genl_family dp_flow_genl_family = { + .id = GENL_ID_GENERATE, + .hdrsize = sizeof(struct ovs_header), + .name = OVS_FLOW_FAMILY, + .version = OVS_FLOW_VERSION, + .maxattr = OVS_FLOW_ATTR_MAX +}; + +static struct genl_multicast_group ovs_dp_flow_multicast_group = { + .name = OVS_FLOW_MCGROUP +}; + +/* Called with genl_lock. */ +static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp, + struct sk_buff *skb, u32 pid, + u32 seq, u32 flags, u8 cmd) +{ + const int skb_orig_len = skb->len; + const struct sw_flow_actions *sf_acts; + struct ovs_flow_stats stats; + struct ovs_header *ovs_header; + struct nlattr *nla; + unsigned long used; + u8 tcp_flags; + int err; + + sf_acts = rcu_dereference_protected(flow->sf_acts, + lockdep_genl_is_held()); + + ovs_header = genlmsg_put(skb, pid, seq, &dp_flow_genl_family, flags, cmd); + if (!ovs_header) + return -EMSGSIZE; + + ovs_header->dp_ifindex = get_dpifindex(dp); + + nla = nla_nest_start(skb, OVS_FLOW_ATTR_KEY); + if (!nla) + goto nla_put_failure; + err = ovs_flow_to_nlattrs(&flow->key, skb); + if (err) + goto error; + nla_nest_end(skb, nla); + + spin_lock_bh(&flow->lock); + used = flow->used; + stats.n_packets = flow->packet_count; + stats.n_bytes = flow->byte_count; + tcp_flags = flow->tcp_flags; + spin_unlock_bh(&flow->lock); + + if (used) + NLA_PUT_U64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used)); + + if (stats.n_packets) + NLA_PUT(skb, OVS_FLOW_ATTR_STATS, + sizeof(struct ovs_flow_stats), &stats); + + if (tcp_flags) + NLA_PUT_U8(skb, OVS_FLOW_ATTR_TCP_FLAGS, tcp_flags); + + /* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if + * this is the first flow to be dumped into 'skb'. This is unusual for + * Netlink but individual action lists can be longer than + * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this. + * The userspace caller can always fetch the actions separately if it + * really wants them. (Most userspace callers in fact don't care.) + * + * This can only fail for dump operations because the skb is always + * properly sized for single flows. + */ + err = nla_put(skb, OVS_FLOW_ATTR_ACTIONS, sf_acts->actions_len, + sf_acts->actions); + if (err < 0 && skb_orig_len) + goto error; + + return genlmsg_end(skb, ovs_header); + +nla_put_failure: + err = -EMSGSIZE; +error: + genlmsg_cancel(skb, ovs_header); + return err; +} + +static struct sk_buff *ovs_flow_cmd_alloc_info(struct sw_flow *flow) +{ + const struct sw_flow_actions *sf_acts; + int len; + + sf_acts = rcu_dereference_protected(flow->sf_acts, + lockdep_genl_is_held()); + + /* OVS_FLOW_ATTR_KEY */ + len = nla_total_size(FLOW_BUFSIZE); + /* OVS_FLOW_ATTR_ACTIONS */ + len += nla_total_size(sf_acts->actions_len); + /* OVS_FLOW_ATTR_STATS */ + len += nla_total_size(sizeof(struct ovs_flow_stats)); + /* OVS_FLOW_ATTR_TCP_FLAGS */ + len += nla_total_size(1); + /* OVS_FLOW_ATTR_USED */ + len += nla_total_size(8); + + len += NLMSG_ALIGN(sizeof(struct ovs_header)); + + return genlmsg_new(len, GFP_KERNEL); +} + +static struct sk_buff *ovs_flow_cmd_build_info(struct sw_flow *flow, + struct datapath *dp, + u32 pid, u32 seq, u8 cmd) +{ + struct sk_buff *skb; + int retval; + + skb = ovs_flow_cmd_alloc_info(flow); + if (!skb) + return ERR_PTR(-ENOMEM); + + retval = ovs_flow_cmd_fill_info(flow, dp, skb, pid, seq, 0, cmd); + BUG_ON(retval < 0); + return skb; +} + +static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info) +{ + struct nlattr **a = info->attrs; + struct ovs_header *ovs_header = info->userhdr; + struct sw_flow_key key; + struct sw_flow *flow; + struct sk_buff *reply; + struct datapath *dp; + struct flow_table *table; + int error; + int key_len; + + /* Extract key. */ + error = -EINVAL; + if (!a[OVS_FLOW_ATTR_KEY]) + goto error; + error = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]); + if (error) + goto error; + + /* Validate actions. */ + if (a[OVS_FLOW_ATTR_ACTIONS]) { + error = validate_actions(a[OVS_FLOW_ATTR_ACTIONS], &key, 0); + if (error) + goto error; + } else if (info->genlhdr->cmd == OVS_FLOW_CMD_NEW) { + error = -EINVAL; + goto error; + } + + dp = get_dp(ovs_header->dp_ifindex); + error = -ENODEV; + if (!dp) + goto error; + + table = genl_dereference(dp->table); + flow = ovs_flow_tbl_lookup(table, &key, key_len); + if (!flow) { + struct sw_flow_actions *acts; + + /* Bail out if we're not allowed to create a new flow. */ + error = -ENOENT; + if (info->genlhdr->cmd == OVS_FLOW_CMD_SET) + goto error; + + /* Expand table, if necessary, to make room. */ + if (ovs_flow_tbl_need_to_expand(table)) { + struct flow_table *new_table; + + new_table = ovs_flow_tbl_expand(table); + if (!IS_ERR(new_table)) { + rcu_assign_pointer(dp->table, new_table); + ovs_flow_tbl_deferred_destroy(table); + table = genl_dereference(dp->table); + } + } + + /* Allocate flow. */ + flow = ovs_flow_alloc(); + if (IS_ERR(flow)) { + error = PTR_ERR(flow); + goto error; + } + flow->key = key; + clear_stats(flow); + + /* Obtain actions. */ + acts = ovs_flow_actions_alloc(a[OVS_FLOW_ATTR_ACTIONS]); + error = PTR_ERR(acts); + if (IS_ERR(acts)) + goto error_free_flow; + rcu_assign_pointer(flow->sf_acts, acts); + + /* Put flow in bucket. */ + flow->hash = ovs_flow_hash(&key, key_len); + ovs_flow_tbl_insert(table, flow); + + reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid, + info->snd_seq, + OVS_FLOW_CMD_NEW); + } else { + /* We found a matching flow. */ + struct sw_flow_actions *old_acts; + struct nlattr *acts_attrs; + + /* Bail out if we're not allowed to modify an existing flow. + * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL + * because Generic Netlink treats the latter as a dump + * request. We also accept NLM_F_EXCL in case that bug ever + * gets fixed. + */ + error = -EEXIST; + if (info->genlhdr->cmd == OVS_FLOW_CMD_NEW && + info->nlhdr->nlmsg_flags & (NLM_F_CREATE | NLM_F_EXCL)) + goto error; + + /* Update actions. */ + old_acts = rcu_dereference_protected(flow->sf_acts, + lockdep_genl_is_held()); + acts_attrs = a[OVS_FLOW_ATTR_ACTIONS]; + if (acts_attrs && + (old_acts->actions_len != nla_len(acts_attrs) || + memcmp(old_acts->actions, nla_data(acts_attrs), + old_acts->actions_len))) { + struct sw_flow_actions *new_acts; + + new_acts = ovs_flow_actions_alloc(acts_attrs); + error = PTR_ERR(new_acts); + if (IS_ERR(new_acts)) + goto error; + + rcu_assign_pointer(flow->sf_acts, new_acts); + ovs_flow_deferred_free_acts(old_acts); + } + + reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid, + info->snd_seq, OVS_FLOW_CMD_NEW); + + /* Clear stats. */ + if (a[OVS_FLOW_ATTR_CLEAR]) { + spin_lock_bh(&flow->lock); + clear_stats(flow); + spin_unlock_bh(&flow->lock); + } + } + + if (!IS_ERR(reply)) + genl_notify(reply, genl_info_net(info), info->snd_pid, + ovs_dp_flow_multicast_group.id, info->nlhdr, + GFP_KERNEL); + else + netlink_set_err(init_net.genl_sock, 0, + ovs_dp_flow_multicast_group.id, PTR_ERR(reply)); + return 0; + +error_free_flow: + ovs_flow_free(flow); +error: + return error; +} + +static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info) +{ + struct nlattr **a = info->attrs; + struct ovs_header *ovs_header = info->userhdr; + struct sw_flow_key key; + struct sk_buff *reply; + struct sw_flow *flow; + struct datapath *dp; + struct flow_table *table; + int err; + int key_len; + + if (!a[OVS_FLOW_ATTR_KEY]) + return -EINVAL; + err = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]); + if (err) + return err; + + dp = get_dp(ovs_header->dp_ifindex); + if (!dp) + return -ENODEV; + + table = genl_dereference(dp->table); + flow = ovs_flow_tbl_lookup(table, &key, key_len); + if (!flow) + return -ENOENT; + + reply = ovs_flow_cmd_build_info(flow, dp, info->snd_pid, + info->snd_seq, OVS_FLOW_CMD_NEW); + if (IS_ERR(reply)) + return PTR_ERR(reply); + + return genlmsg_reply(reply, info); +} + +static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info) +{ + struct nlattr **a = info->attrs; + struct ovs_header *ovs_header = info->userhdr; + struct sw_flow_key key; + struct sk_buff *reply; + struct sw_flow *flow; + struct datapath *dp; + struct flow_table *table; + int err; + int key_len; + + if (!a[OVS_FLOW_ATTR_KEY]) + return flush_flows(ovs_header->dp_ifindex); + err = ovs_flow_from_nlattrs(&key, &key_len, a[OVS_FLOW_ATTR_KEY]); + if (err) + return err; + + dp = get_dp(ovs_header->dp_ifindex); + if (!dp) + return -ENODEV; + + table = genl_dereference(dp->table); + flow = ovs_flow_tbl_lookup(table, &key, key_len); + if (!flow) + return -ENOENT; + + reply = ovs_flow_cmd_alloc_info(flow); + if (!reply) + return -ENOMEM; + + ovs_flow_tbl_remove(table, flow); + + err = ovs_flow_cmd_fill_info(flow, dp, reply, info->snd_pid, + info->snd_seq, 0, OVS_FLOW_CMD_DEL); + BUG_ON(err < 0); + + ovs_flow_deferred_free(flow); + + genl_notify(reply, genl_info_net(info), info->snd_pid, + ovs_dp_flow_multicast_group.id, info->nlhdr, GFP_KERNEL); + return 0; +} + +static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh)); + struct datapath *dp; + struct flow_table *table; + + dp = get_dp(ovs_header->dp_ifindex); + if (!dp) + return -ENODEV; + + table = genl_dereference(dp->table); + + for (;;) { + struct sw_flow *flow; + u32 bucket, obj; + + bucket = cb->args[0]; + obj = cb->args[1]; + flow = ovs_flow_tbl_next(table, &bucket, &obj); + if (!flow) + break; + + if (ovs_flow_cmd_fill_info(flow, dp, skb, + NETLINK_CB(cb->skb).pid, + cb->nlh->nlmsg_seq, NLM_F_MULTI, + OVS_FLOW_CMD_NEW) < 0) + break; + + cb->args[0] = bucket; + cb->args[1] = obj; + } + return skb->len; +} + +static struct genl_ops dp_flow_genl_ops[] = { + { .cmd = OVS_FLOW_CMD_NEW, + .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */ + .policy = flow_policy, + .doit = ovs_flow_cmd_new_or_set + }, + { .cmd = OVS_FLOW_CMD_DEL, + .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */ + .policy = flow_policy, + .doit = ovs_flow_cmd_del + }, + { .cmd = OVS_FLOW_CMD_GET, + .flags = 0, /* OK for unprivileged users. */ + .policy = flow_policy, + .doit = ovs_flow_cmd_get, + .dumpit = ovs_flow_cmd_dump + }, + { .cmd = OVS_FLOW_CMD_SET, + .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */ + .policy = flow_policy, + .doit = ovs_flow_cmd_new_or_set, + }, +}; + +static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = { + [OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 }, + [OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 }, +}; + +static struct genl_family dp_datapath_genl_family = { + .id = GENL_ID_GENERATE, + .hdrsize = sizeof(struct ovs_header), + .name = OVS_DATAPATH_FAMILY, + .version = OVS_DATAPATH_VERSION, + .maxattr = OVS_DP_ATTR_MAX +}; + +static struct genl_multicast_group ovs_dp_datapath_multicast_group = { + .name = OVS_DATAPATH_MCGROUP +}; + +static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb, + u32 pid, u32 seq, u32 flags, u8 cmd) +{ + struct ovs_header *ovs_header; + struct ovs_dp_stats dp_stats; + int err; + + ovs_header = genlmsg_put(skb, pid, seq, &dp_datapath_genl_family, + flags, cmd); + if (!ovs_header) + goto error; + + ovs_header->dp_ifindex = get_dpifindex(dp); + + rcu_read_lock(); + err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp)); + rcu_read_unlock(); + if (err) + goto nla_put_failure; + + get_dp_stats(dp, &dp_stats); + NLA_PUT(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats), &dp_stats); + + return genlmsg_end(skb, ovs_header); + +nla_put_failure: + genlmsg_cancel(skb, ovs_header); +error: + return -EMSGSIZE; +} + +static struct sk_buff *ovs_dp_cmd_build_info(struct datapath *dp, u32 pid, + u32 seq, u8 cmd) +{ + struct sk_buff *skb; + int retval; + + skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!skb) + return ERR_PTR(-ENOMEM); + + retval = ovs_dp_cmd_fill_info(dp, skb, pid, seq, 0, cmd); + if (retval < 0) { + kfree_skb(skb); + return ERR_PTR(retval); + } + return skb; +} + +/* Called with genl_mutex and optionally with RTNL lock also. */ +static struct datapath *lookup_datapath(struct ovs_header *ovs_header, + struct nlattr *a[OVS_DP_ATTR_MAX + 1]) +{ + struct datapath *dp; + + if (!a[OVS_DP_ATTR_NAME]) + dp = get_dp(ovs_header->dp_ifindex); + else { + struct vport *vport; + + rcu_read_lock(); + vport = ovs_vport_locate(nla_data(a[OVS_DP_ATTR_NAME])); + dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL; + rcu_read_unlock(); + } + return dp ? dp : ERR_PTR(-ENODEV); +} + +static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info) +{ + struct nlattr **a = info->attrs; + struct vport_parms parms; + struct sk_buff *reply; + struct datapath *dp; + struct vport *vport; + int err; + + err = -EINVAL; + if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID]) + goto err; + + rtnl_lock(); + err = -ENODEV; + if (!try_module_get(THIS_MODULE)) + goto err_unlock_rtnl; + + err = -ENOMEM; + dp = kzalloc(sizeof(*dp), GFP_KERNEL); + if (dp == NULL) + goto err_put_ |