diff options
author | Simon Horman | 2014-10-06 05:05:13 -0700 |
---|---|---|
committer | Pravin B Shelar | 2014-11-05 23:52:33 -0800 |
commit | 25cd9ba0abc0749e5cb78e6493c6f6b3311ec6c5 (patch) | |
tree | fbfb953b27fbdcc27d0a50a6e3444532f51f5ffa /net/openvswitch | |
parent | 59b93b41e7fa71138734a911b11b044340dd16bd (diff) |
openvswitch: Add basic MPLS support to kernel
Allow datapath to recognize and extract MPLS labels into flow keys
and execute actions which push, pop, and set labels on packets.
Based heavily on work by Leo Alterman, Ravi K, Isaku Yamahata and Joe Stringer.
Cc: Ravi K <rkerur@gmail.com>
Cc: Leo Alterman <lalterman@nicira.com>
Cc: Isaku Yamahata <yamahata@valinux.co.jp>
Cc: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Diffstat (limited to 'net/openvswitch')
-rw-r--r-- | net/openvswitch/Kconfig | 1 | ||||
-rw-r--r-- | net/openvswitch/actions.c | 106 | ||||
-rw-r--r-- | net/openvswitch/datapath.c | 6 | ||||
-rw-r--r-- | net/openvswitch/flow.c | 30 | ||||
-rw-r--r-- | net/openvswitch/flow.h | 17 | ||||
-rw-r--r-- | net/openvswitch/flow_netlink.c | 139 | ||||
-rw-r--r-- | net/openvswitch/flow_netlink.h | 2 |
7 files changed, 272 insertions, 29 deletions
diff --git a/net/openvswitch/Kconfig b/net/openvswitch/Kconfig index 2a9673e39ca1..454ce12efbbf 100644 --- a/net/openvswitch/Kconfig +++ b/net/openvswitch/Kconfig @@ -30,6 +30,7 @@ config OPENVSWITCH config OPENVSWITCH_GRE tristate "Open vSwitch GRE tunneling support" + select NET_MPLS_GSO depends on INET depends on OPENVSWITCH depends on NET_IPGRE_DEMUX diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c index 922c133b1933..930b1b6e4cef 100644 --- a/net/openvswitch/actions.c +++ b/net/openvswitch/actions.c @@ -28,10 +28,12 @@ #include <linux/in6.h> #include <linux/if_arp.h> #include <linux/if_vlan.h> + #include <net/ip.h> #include <net/ipv6.h> #include <net/checksum.h> #include <net/dsfield.h> +#include <net/mpls.h> #include <net/sctp/checksum.h> #include "datapath.h" @@ -118,6 +120,92 @@ static int make_writable(struct sk_buff *skb, int write_len) return pskb_expand_head(skb, 0, 0, GFP_ATOMIC); } +static int push_mpls(struct sk_buff *skb, + const struct ovs_action_push_mpls *mpls) +{ + __be32 *new_mpls_lse; + struct ethhdr *hdr; + + /* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */ + if (skb->encapsulation) + return -ENOTSUPP; + + if (skb_cow_head(skb, MPLS_HLEN) < 0) + return -ENOMEM; + + skb_push(skb, MPLS_HLEN); + memmove(skb_mac_header(skb) - MPLS_HLEN, skb_mac_header(skb), + skb->mac_len); + skb_reset_mac_header(skb); + + new_mpls_lse = (__be32 *)skb_mpls_header(skb); + *new_mpls_lse = mpls->mpls_lse; + + if (skb->ip_summed == CHECKSUM_COMPLETE) + skb->csum = csum_add(skb->csum, csum_partial(new_mpls_lse, + MPLS_HLEN, 0)); + + hdr = eth_hdr(skb); + hdr->h_proto = mpls->mpls_ethertype; + + skb_set_inner_protocol(skb, skb->protocol); + skb->protocol = mpls->mpls_ethertype; + + return 0; +} + +static int pop_mpls(struct sk_buff *skb, const __be16 ethertype) +{ + struct ethhdr *hdr; + int err; + + err = make_writable(skb, skb->mac_len + MPLS_HLEN); + if (unlikely(err)) + return err; + + if (skb->ip_summed == CHECKSUM_COMPLETE) + skb->csum = csum_sub(skb->csum, + csum_partial(skb_mpls_header(skb), + MPLS_HLEN, 0)); + + memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb), + skb->mac_len); + + __skb_pull(skb, MPLS_HLEN); + skb_reset_mac_header(skb); + + /* skb_mpls_header() is used to locate the ethertype + * field correctly in the presence of VLAN tags. + */ + hdr = (struct ethhdr *)(skb_mpls_header(skb) - ETH_HLEN); + hdr->h_proto = ethertype; + if (eth_p_mpls(skb->protocol)) + skb->protocol = ethertype; + return 0; +} + +static int set_mpls(struct sk_buff *skb, const __be32 *mpls_lse) +{ + __be32 *stack; + int err; + + err = make_writable(skb, skb->mac_len + MPLS_HLEN); + if (unlikely(err)) + return err; + + stack = (__be32 *)skb_mpls_header(skb); + if (skb->ip_summed == CHECKSUM_COMPLETE) { + __be32 diff[] = { ~(*stack), *mpls_lse }; + + skb->csum = ~csum_partial((char *)diff, sizeof(diff), + ~skb->csum); + } + + *stack = *mpls_lse; + + return 0; +} + /* remove VLAN header from packet and update csum accordingly. */ static int __pop_vlan_tci(struct sk_buff *skb, __be16 *current_tci) { @@ -140,10 +228,12 @@ static int __pop_vlan_tci(struct sk_buff *skb, __be16 *current_tci) vlan_set_encap_proto(skb, vhdr); skb->mac_header += VLAN_HLEN; + if (skb_network_offset(skb) < ETH_HLEN) skb_set_network_header(skb, ETH_HLEN); - skb_reset_mac_len(skb); + /* Update mac_len for subsequent MPLS actions */ + skb_reset_mac_len(skb); return 0; } @@ -186,6 +276,8 @@ static int push_vlan(struct sk_buff *skb, const struct ovs_action_push_vlan *vla if (!__vlan_put_tag(skb, skb->vlan_proto, current_tag)) return -ENOMEM; + /* Update mac_len for subsequent MPLS actions */ + skb->mac_len += VLAN_HLEN; if (skb->ip_summed == CHECKSUM_COMPLETE) skb->csum = csum_add(skb->csum, csum_partial(skb->data @@ -612,6 +704,10 @@ static int execute_set_action(struct sk_buff *skb, case OVS_KEY_ATTR_SCTP: err = set_sctp(skb, nla_data(nested_attr)); break; + + case OVS_KEY_ATTR_MPLS: + err = set_mpls(skb, nla_data(nested_attr)); + break; } return err; @@ -690,6 +786,14 @@ static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, execute_hash(skb, key, a); break; + case OVS_ACTION_ATTR_PUSH_MPLS: + err = push_mpls(skb, nla_data(a)); + break; + + case OVS_ACTION_ATTR_POP_MPLS: + err = pop_mpls(skb, nla_get_be16(a)); + break; + case OVS_ACTION_ATTR_PUSH_VLAN: err = push_vlan(skb, nla_data(a)); if (unlikely(err)) /* skb already freed. */ diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c index f18302f32049..688cb9bc0ef1 100644 --- a/net/openvswitch/datapath.c +++ b/net/openvswitch/datapath.c @@ -560,7 +560,7 @@ static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info) goto err_flow_free; err = ovs_nla_copy_actions(a[OVS_PACKET_ATTR_ACTIONS], - &flow->key, 0, &acts); + &flow->key, &acts); if (err) goto err_flow_free; @@ -846,7 +846,7 @@ static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info) goto err_kfree_flow; error = ovs_nla_copy_actions(a[OVS_FLOW_ATTR_ACTIONS], &new_flow->key, - 0, &acts); + &acts); if (error) { OVS_NLERR("Flow actions may not be safe on all matching packets.\n"); goto err_kfree_acts; @@ -953,7 +953,7 @@ static struct sw_flow_actions *get_flow_actions(const struct nlattr *a, return acts; ovs_flow_mask_key(&masked_key, key, mask); - error = ovs_nla_copy_actions(a, &masked_key, 0, &acts); + error = ovs_nla_copy_actions(a, &masked_key, &acts); if (error) { OVS_NLERR("Flow actions may not be safe on all matching packets.\n"); kfree(acts); diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c index 2b78789ea7c5..90a21010fc8f 100644 --- a/net/openvswitch/flow.c +++ b/net/openvswitch/flow.c @@ -32,6 +32,7 @@ #include <linux/if_arp.h> #include <linux/ip.h> #include <linux/ipv6.h> +#include <linux/mpls.h> #include <linux/sctp.h> #include <linux/smp.h> #include <linux/tcp.h> @@ -42,6 +43,7 @@ #include <net/ip.h> #include <net/ip_tunnels.h> #include <net/ipv6.h> +#include <net/mpls.h> #include <net/ndisc.h> #include "datapath.h" @@ -480,6 +482,7 @@ static int key_extract(struct sk_buff *skb, struct sw_flow_key *key) return -ENOMEM; skb_reset_network_header(skb); + skb_reset_mac_len(skb); __skb_push(skb, skb->data - skb_mac_header(skb)); /* Network layer. */ @@ -584,6 +587,33 @@ static int key_extract(struct sk_buff *skb, struct sw_flow_key *key) memset(&key->ip, 0, sizeof(key->ip)); memset(&key->ipv4, 0, sizeof(key->ipv4)); } + } else if (eth_p_mpls(key->eth.type)) { + size_t stack_len = MPLS_HLEN; + + /* In the presence of an MPLS label stack the end of the L2 + * header and the beginning of the L3 header differ. + * + * Advance network_header to the beginning of the L3 + * header. mac_len corresponds to the end of the L2 header. + */ + while (1) { + __be32 lse; + + error = check_header(skb, skb->mac_len + stack_len); + if (unlikely(error)) + return 0; + + memcpy(&lse, skb_network_header(skb), MPLS_HLEN); + + if (stack_len == MPLS_HLEN) + memcpy(&key->mpls.top_lse, &lse, MPLS_HLEN); + + skb_set_network_header(skb, skb->mac_len + stack_len); + if (lse & htonl(MPLS_LS_S_MASK)) + break; + + stack_len += MPLS_HLEN; + } } else if (key->eth.type == htons(ETH_P_IPV6)) { int nh_len; /* IPv6 Header + Extensions */ diff --git a/net/openvswitch/flow.h b/net/openvswitch/flow.h index 71813318c8c7..4962bee81a11 100644 --- a/net/openvswitch/flow.h +++ b/net/openvswitch/flow.h @@ -102,12 +102,17 @@ struct sw_flow_key { __be16 tci; /* 0 if no VLAN, VLAN_TAG_PRESENT set otherwise. */ __be16 type; /* Ethernet frame type. */ } eth; - struct { - u8 proto; /* IP protocol or lower 8 bits of ARP opcode. */ - u8 tos; /* IP ToS. */ - u8 ttl; /* IP TTL/hop limit. */ - u8 frag; /* One of OVS_FRAG_TYPE_*. */ - } ip; + union { + struct { + __be32 top_lse; /* top label stack entry */ + } mpls; + struct { + u8 proto; /* IP protocol or lower 8 bits of ARP opcode. */ + u8 tos; /* IP ToS. */ + u8 ttl; /* IP TTL/hop limit. */ + u8 frag; /* One of OVS_FRAG_TYPE_*. */ + } ip; + }; struct { __be16 src; /* TCP/UDP/SCTP source port. */ __be16 dst; /* TCP/UDP/SCTP destination port. */ diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c index 939bcb32100f..569309c49cc0 100644 --- a/net/openvswitch/flow_netlink.c +++ b/net/openvswitch/flow_netlink.c @@ -46,6 +46,7 @@ #include <net/ip.h> #include <net/ipv6.h> #include <net/ndisc.h> +#include <net/mpls.h> #include "flow_netlink.h" @@ -134,7 +135,8 @@ static bool match_validate(const struct sw_flow_match *match, | (1 << OVS_KEY_ATTR_ICMP) | (1 << OVS_KEY_ATTR_ICMPV6) | (1 << OVS_KEY_ATTR_ARP) - | (1 << OVS_KEY_ATTR_ND)); + | (1 << OVS_KEY_ATTR_ND) + | (1 << OVS_KEY_ATTR_MPLS)); /* Always allowed mask fields. */ mask_allowed |= ((1 << OVS_KEY_ATTR_TUNNEL) @@ -149,6 +151,12 @@ static bool match_validate(const struct sw_flow_match *match, mask_allowed |= 1 << OVS_KEY_ATTR_ARP; } + if (eth_p_mpls(match->key->eth.type)) { + key_expected |= 1 << OVS_KEY_ATTR_MPLS; + if (match->mask && (match->mask->key.eth.type == htons(0xffff))) + mask_allowed |= 1 << OVS_KEY_ATTR_MPLS; + } + if (match->key->eth.type == htons(ETH_P_IP)) { key_expected |= 1 << OVS_KEY_ATTR_IPV4; if (match->mask && (match->mask->key.eth.type == htons(0xffff))) @@ -266,6 +274,7 @@ static const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = { [OVS_KEY_ATTR_RECIRC_ID] = sizeof(u32), [OVS_KEY_ATTR_DP_HASH] = sizeof(u32), [OVS_KEY_ATTR_TUNNEL] = -1, + [OVS_KEY_ATTR_MPLS] = sizeof(struct ovs_key_mpls), }; static bool is_all_zero(const u8 *fp, size_t size) @@ -735,6 +744,16 @@ static int ovs_key_from_nlattrs(struct sw_flow_match *match, u64 attrs, attrs &= ~(1 << OVS_KEY_ATTR_ARP); } + if (attrs & (1 << OVS_KEY_ATTR_MPLS)) { + const struct ovs_key_mpls *mpls_key; + + mpls_key = nla_data(a[OVS_KEY_ATTR_MPLS]); + SW_FLOW_KEY_PUT(match, mpls.top_lse, + mpls_key->mpls_lse, is_mask); + + attrs &= ~(1 << OVS_KEY_ATTR_MPLS); + } + if (attrs & (1 << OVS_KEY_ATTR_TCP)) { const struct ovs_key_tcp *tcp_key; @@ -1140,6 +1159,14 @@ int ovs_nla_put_flow(const struct sw_flow_key *swkey, arp_key->arp_op = htons(output->ip.proto); ether_addr_copy(arp_key->arp_sha, output->ipv4.arp.sha); ether_addr_copy(arp_key->arp_tha, output->ipv4.arp.tha); + } else if (eth_p_mpls(swkey->eth.type)) { + struct ovs_key_mpls *mpls_key; + + nla = nla_reserve(skb, OVS_KEY_ATTR_MPLS, sizeof(*mpls_key)); + if (!nla) + goto nla_put_failure; + mpls_key = nla_data(nla); + mpls_key->mpls_lse = output->mpls.top_lse; } if ((swkey->eth.type == htons(ETH_P_IP) || @@ -1336,9 +1363,15 @@ static inline void add_nested_action_end(struct sw_flow_actions *sfa, a->nla_len = sfa->actions_len - st_offset; } +static int ovs_nla_copy_actions__(const struct nlattr *attr, + const struct sw_flow_key *key, + int depth, struct sw_flow_actions **sfa, + __be16 eth_type, __be16 vlan_tci); + static int validate_and_copy_sample(const struct nlattr *attr, const struct sw_flow_key *key, int depth, - struct sw_flow_actions **sfa) + struct sw_flow_actions **sfa, + __be16 eth_type, __be16 vlan_tci) { const struct nlattr *attrs[OVS_SAMPLE_ATTR_MAX + 1]; const struct nlattr *probability, *actions; @@ -1375,7 +1408,8 @@ static int validate_and_copy_sample(const struct nlattr *attr, if (st_acts < 0) return st_acts; - err = ovs_nla_copy_actions(actions, key, depth + 1, sfa); + err = ovs_nla_copy_actions__(actions, key, depth + 1, sfa, + eth_type, vlan_tci); if (err) return err; @@ -1385,10 +1419,10 @@ static int validate_and_copy_sample(const struct nlattr *attr, return 0; } -static int validate_tp_port(const struct sw_flow_key *flow_key) +static int validate_tp_port(const struct sw_flow_key *flow_key, + __be16 eth_type) { - if ((flow_key->eth.type == htons(ETH_P_IP) || - flow_key->eth.type == htons(ETH_P_IPV6)) && + if ((eth_type == htons(ETH_P_IP) || eth_type == htons(ETH_P_IPV6)) && (flow_key->tp.src || flow_key->tp.dst)) return 0; @@ -1483,7 +1517,7 @@ static int validate_and_copy_set_tun(const struct nlattr *attr, static int validate_set(const struct nlattr *a, const struct sw_flow_key *flow_key, struct sw_flow_actions **sfa, - bool *set_tun) + bool *set_tun, __be16 eth_type) { const struct nlattr *ovs_key = nla_data(a); int key_type = nla_type(ovs_key); @@ -1508,6 +1542,9 @@ static int validate_set(const struct nlattr *a, break; case OVS_KEY_ATTR_TUNNEL: + if (eth_p_mpls(eth_type)) + return -EINVAL; + *set_tun = true; err = validate_and_copy_set_tun(a, sfa); if (err) @@ -1515,7 +1552,7 @@ static int validate_set(const struct nlattr *a, break; case OVS_KEY_ATTR_IPV4: - if (flow_key->eth.type != htons(ETH_P_IP)) + if (eth_type != htons(ETH_P_IP)) return -EINVAL; if (!flow_key->ip.proto) @@ -1531,7 +1568,7 @@ static int validate_set(const struct nlattr *a, break; case OVS_KEY_ATTR_IPV6: - if (flow_key->eth.type != htons(ETH_P_IPV6)) + if (eth_type != htons(ETH_P_IPV6)) return -EINVAL; if (!flow_key->ip.proto) @@ -1553,19 +1590,24 @@ static int validate_set(const struct nlattr *a, if (flow_key->ip.proto != IPPROTO_TCP) return -EINVAL; - return validate_tp_port(flow_key); + return validate_tp_port(flow_key, eth_type); case OVS_KEY_ATTR_UDP: if (flow_key->ip.proto != IPPROTO_UDP) return -EINVAL; - return validate_tp_port(flow_key); + return validate_tp_port(flow_key, eth_type); + + case OVS_KEY_ATTR_MPLS: + if (!eth_p_mpls(eth_type)) + return -EINVAL; + break; case OVS_KEY_ATTR_SCTP: if (flow_key->ip.proto != IPPROTO_SCTP) return -EINVAL; - return validate_tp_port(flow_key); + return validate_tp_port(flow_key, eth_type); default: return -EINVAL; @@ -1609,12 +1651,13 @@ static int copy_action(const struct nlattr *from, return 0; } -int ovs_nla_copy_actions(const struct nlattr *attr, - const struct sw_flow_key *key, - int depth, - struct sw_flow_actions **sfa) +static int ovs_nla_copy_actions__(const struct nlattr *attr, + const struct sw_flow_key *key, + int depth, struct sw_flow_actions **sfa, + __be16 eth_type, __be16 vlan_tci) { const struct nlattr *a; + bool out_tnl_port = false; int rem, err; if (depth >= SAMPLE_ACTION_DEPTH) @@ -1626,6 +1669,8 @@ int ovs_nla_copy_actions(const struct nlattr *attr, [OVS_ACTION_ATTR_OUTPUT] = sizeof(u32), [OVS_ACTION_ATTR_RECIRC] = sizeof(u32), [OVS_ACTION_ATTR_USERSPACE] = (u32)-1, + [OVS_ACTION_ATTR_PUSH_MPLS] = sizeof(struct ovs_action_push_mpls), + [OVS_ACTION_ATTR_POP_MPLS] = sizeof(__be16), [OVS_ACTION_ATTR_PUSH_VLAN] = sizeof(struct ovs_action_push_vlan), [OVS_ACTION_ATTR_POP_VLAN] = 0, [OVS_ACTION_ATTR_SET] = (u32)-1, @@ -1655,6 +1700,8 @@ int ovs_nla_copy_actions(const struct nlattr *attr, case OVS_ACTION_ATTR_OUTPUT: if (nla_get_u32(a) >= DP_MAX_PORTS) return -EINVAL; + out_tnl_port = false; + break; case OVS_ACTION_ATTR_HASH: { @@ -1671,6 +1718,7 @@ int ovs_nla_copy_actions(const struct nlattr *attr, } case OVS_ACTION_ATTR_POP_VLAN: + vlan_tci = htons(0); break; case OVS_ACTION_ATTR_PUSH_VLAN: @@ -1679,19 +1727,66 @@ int ovs_nla_copy_actions(const struct nlattr *attr, return -EINVAL; if (!(vlan->vlan_tci & htons(VLAN_TAG_PRESENT))) return -EINVAL; + vlan_tci = vlan->vlan_tci; break; case OVS_ACTION_ATTR_RECIRC: break; + case OVS_ACTION_ATTR_PUSH_MPLS: { + const struct ovs_action_push_mpls *mpls = nla_data(a); + + /* Networking stack do not allow simultaneous Tunnel + * and MPLS GSO. + */ + if (out_tnl_port) + return -EINVAL; + + if (!eth_p_mpls(mpls->mpls_ethertype)) + return -EINVAL; + /* Prohibit push MPLS other than to a white list + * for packets that have a known tag order. + */ + if (vlan_tci & htons(VLAN_TAG_PRESENT) || + (eth_type != htons(ETH_P_IP) && + eth_type != htons(ETH_P_IPV6) && + eth_type != htons(ETH_P_ARP) && + eth_type != htons(ETH_P_RARP) && + !eth_p_mpls(eth_type))) + return -EINVAL; + eth_type = mpls->mpls_ethertype; + break; + } + + case OVS_ACTION_ATTR_POP_MPLS: + if (vlan_tci & htons(VLAN_TAG_PRESENT) || + !eth_p_mpls(eth_type)) + return -EINVAL; + + /* Disallow subsequent L2.5+ set and mpls_pop actions + * as there is no check here to ensure that the new + * eth_type is valid and thus set actions could + * write off the end of the packet or otherwise + * corrupt it. + * + * Support for these actions is planned using packet + * recirculation. + */ + eth_type = htons(0); + break; + case OVS_ACTION_ATTR_SET: - err = validate_set(a, key, sfa, &skip_copy); + err = validate_set(a, key, sfa, + &out_tnl_port, eth_type); if (err) return err; + + skip_copy = out_tnl_port; break; case OVS_ACTION_ATTR_SAMPLE: - err = validate_and_copy_sample(a, key, depth, sfa); + err = validate_and_copy_sample(a, key, depth, sfa, + eth_type, vlan_tci); if (err) return err; skip_copy = true; @@ -1713,6 +1808,14 @@ int ovs_nla_copy_actions(const struct nlattr *attr, return 0; } +int ovs_nla_copy_actions(const struct nlattr *attr, + const struct sw_flow_key *key, + struct sw_flow_actions **sfa) +{ + return ovs_nla_copy_actions__(attr, key, 0, sfa, key->eth.type, + key->eth.tci); +} + static int sample_action_to_attr(const struct nlattr *attr, struct sk_buff *skb) { const struct nlattr *a; diff --git a/net/openvswitch/flow_netlink.h b/net/openvswitch/flow_netlink.h index 206e45add888..6355b1d01329 100644 --- a/net/openvswitch/flow_netlink.h +++ b/net/openvswitch/flow_netlink.h @@ -49,7 +49,7 @@ int ovs_nla_get_match(struct sw_flow_match *match, const struct nlattr *); int ovs_nla_copy_actions(const struct nlattr *attr, - const struct sw_flow_key *key, int depth, + const struct sw_flow_key *key, struct sw_flow_actions **sfa); int ovs_nla_put_actions(const struct nlattr *attr, int len, struct sk_buff *skb); |