diff options
Diffstat (limited to 'kernel/net/mpls')
| -rw-r--r-- | kernel/net/mpls/Kconfig | 8 | ||||
| -rw-r--r-- | kernel/net/mpls/Makefile | 1 | ||||
| -rw-r--r-- | kernel/net/mpls/af_mpls.c | 796 | ||||
| -rw-r--r-- | kernel/net/mpls/internal.h | 81 | ||||
| -rw-r--r-- | kernel/net/mpls/mpls_gso.c | 2 | ||||
| -rw-r--r-- | kernel/net/mpls/mpls_iptunnel.c | 231 |
6 files changed, 951 insertions, 168 deletions
diff --git a/kernel/net/mpls/Kconfig b/kernel/net/mpls/Kconfig index 17bde799c..5c467ef97 100644 --- a/kernel/net/mpls/Kconfig +++ b/kernel/net/mpls/Kconfig @@ -24,7 +24,13 @@ config NET_MPLS_GSO config MPLS_ROUTING tristate "MPLS: routing support" - help + ---help--- Add support for forwarding of mpls packets. +config MPLS_IPTUNNEL + tristate "MPLS: IP over MPLS tunnel support" + depends on LWTUNNEL && MPLS_ROUTING + ---help--- + mpls ip tunnel support. + endif # MPLS diff --git a/kernel/net/mpls/Makefile b/kernel/net/mpls/Makefile index 65bbe68c7..9ca923625 100644 --- a/kernel/net/mpls/Makefile +++ b/kernel/net/mpls/Makefile @@ -3,5 +3,6 @@ # obj-$(CONFIG_NET_MPLS_GSO) += mpls_gso.o obj-$(CONFIG_MPLS_ROUTING) += mpls_router.o +obj-$(CONFIG_MPLS_IPTUNNEL) += mpls_iptunnel.o mpls_router-y := af_mpls.o diff --git a/kernel/net/mpls/af_mpls.c b/kernel/net/mpls/af_mpls.c index 1f93a5978..c32fc411a 100644 --- a/kernel/net/mpls/af_mpls.c +++ b/kernel/net/mpls/af_mpls.c @@ -15,24 +15,19 @@ #include <net/ip_fib.h> #include <net/netevent.h> #include <net/netns/generic.h> +#if IS_ENABLED(CONFIG_IPV6) +#include <net/ipv6.h> +#include <net/addrconf.h> +#endif +#include <net/nexthop.h> #include "internal.h" -#define LABEL_NOT_SPECIFIED (1<<20) -#define MAX_NEW_LABELS 2 - -/* This maximum ha length copied from the definition of struct neighbour */ -#define MAX_VIA_ALEN (ALIGN(MAX_ADDR_LEN, sizeof(unsigned long))) - -struct mpls_route { /* next hop label forwarding entry */ - struct net_device __rcu *rt_dev; - struct rcu_head rt_rcu; - u32 rt_label[MAX_NEW_LABELS]; - u8 rt_protocol; /* routing protocol that set this entry */ - u8 rt_labels; - u8 rt_via_alen; - u8 rt_via_table; - u8 rt_via[0]; -}; +/* Maximum number of labels to look ahead at when selecting a path of + * a multipath route + */ +#define MAX_MP_SELECT_LABELS 4 + +#define MPLS_NEIGH_TABLE_UNSPEC (NEIGH_LINK_TABLE + 1) static int zero = 0; static int label_limit = (1 << 20) - 1; @@ -58,24 +53,40 @@ static inline struct mpls_dev *mpls_dev_get(const struct net_device *dev) return rcu_dereference_rtnl(dev->mpls_ptr); } -static bool mpls_output_possible(const struct net_device *dev) +bool mpls_output_possible(const struct net_device *dev) { return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev); } +EXPORT_SYMBOL_GPL(mpls_output_possible); + +static u8 *__mpls_nh_via(struct mpls_route *rt, struct mpls_nh *nh) +{ + u8 *nh0_via = PTR_ALIGN((u8 *)&rt->rt_nh[rt->rt_nhn], VIA_ALEN_ALIGN); + int nh_index = nh - rt->rt_nh; + + return nh0_via + rt->rt_max_alen * nh_index; +} + +static const u8 *mpls_nh_via(const struct mpls_route *rt, + const struct mpls_nh *nh) +{ + return __mpls_nh_via((struct mpls_route *)rt, (struct mpls_nh *)nh); +} -static unsigned int mpls_rt_header_size(const struct mpls_route *rt) +static unsigned int mpls_nh_header_size(const struct mpls_nh *nh) { /* The size of the layer 2.5 labels to be added for this route */ - return rt->rt_labels * sizeof(struct mpls_shim_hdr); + return nh->nh_labels * sizeof(struct mpls_shim_hdr); } -static unsigned int mpls_dev_mtu(const struct net_device *dev) +unsigned int mpls_dev_mtu(const struct net_device *dev) { /* The amount of data the layer 2 frame can hold */ return dev->mtu; } +EXPORT_SYMBOL_GPL(mpls_dev_mtu); -static bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu) +bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu) { if (skb->len <= mtu) return false; @@ -85,20 +96,87 @@ static bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu) return true; } +EXPORT_SYMBOL_GPL(mpls_pkt_too_big); + +static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt, + struct sk_buff *skb, bool bos) +{ + struct mpls_entry_decoded dec; + struct mpls_shim_hdr *hdr; + bool eli_seen = false; + int label_index; + int nh_index = 0; + u32 hash = 0; + + /* No need to look further into packet if there's only + * one path + */ + if (rt->rt_nhn == 1) + goto out; + + for (label_index = 0; label_index < MAX_MP_SELECT_LABELS && !bos; + label_index++) { + if (!pskb_may_pull(skb, sizeof(*hdr) * label_index)) + break; + + /* Read and decode the current label */ + hdr = mpls_hdr(skb) + label_index; + dec = mpls_entry_decode(hdr); + + /* RFC6790 - reserved labels MUST NOT be used as keys + * for the load-balancing function + */ + if (likely(dec.label >= MPLS_LABEL_FIRST_UNRESERVED)) { + hash = jhash_1word(dec.label, hash); + + /* The entropy label follows the entropy label + * indicator, so this means that the entropy + * label was just added to the hash - no need to + * go any deeper either in the label stack or in the + * payload + */ + if (eli_seen) + break; + } else if (dec.label == MPLS_LABEL_ENTROPY) { + eli_seen = true; + } + + bos = dec.bos; + if (bos && pskb_may_pull(skb, sizeof(*hdr) * label_index + + sizeof(struct iphdr))) { + const struct iphdr *v4hdr; + + v4hdr = (const struct iphdr *)(mpls_hdr(skb) + + label_index); + if (v4hdr->version == 4) { + hash = jhash_3words(ntohl(v4hdr->saddr), + ntohl(v4hdr->daddr), + v4hdr->protocol, hash); + } else if (v4hdr->version == 6 && + pskb_may_pull(skb, sizeof(*hdr) * label_index + + sizeof(struct ipv6hdr))) { + const struct ipv6hdr *v6hdr; + + v6hdr = (const struct ipv6hdr *)(mpls_hdr(skb) + + label_index); + + hash = __ipv6_addr_jhash(&v6hdr->saddr, hash); + hash = __ipv6_addr_jhash(&v6hdr->daddr, hash); + hash = jhash_1word(v6hdr->nexthdr, hash); + } + } + } + + nh_index = hash % rt->rt_nhn; +out: + return &rt->rt_nh[nh_index]; +} static bool mpls_egress(struct mpls_route *rt, struct sk_buff *skb, struct mpls_entry_decoded dec) { - /* RFC4385 and RFC5586 encode other packets in mpls such that - * they don't conflict with the ip version number, making - * decoding by examining the ip version correct in everything - * except for the strangest cases. - * - * The strange cases if we choose to support them will require - * manual configuration. - */ - struct iphdr *hdr4; - bool success = true; + enum mpls_payload_type payload_type; + bool success = false; /* The IPv4 code below accesses through the IPv4 header * checksum, which is 12 bytes into the packet. @@ -113,23 +191,32 @@ static bool mpls_egress(struct mpls_route *rt, struct sk_buff *skb, if (!pskb_may_pull(skb, 12)) return false; - /* Use ip_hdr to find the ip protocol version */ - hdr4 = ip_hdr(skb); - if (hdr4->version == 4) { + payload_type = rt->rt_payload_type; + if (payload_type == MPT_UNSPEC) + payload_type = ip_hdr(skb)->version; + + switch (payload_type) { + case MPT_IPV4: { + struct iphdr *hdr4 = ip_hdr(skb); skb->protocol = htons(ETH_P_IP); csum_replace2(&hdr4->check, htons(hdr4->ttl << 8), htons(dec.ttl << 8)); hdr4->ttl = dec.ttl; + success = true; + break; } - else if (hdr4->version == 6) { + case MPT_IPV6: { struct ipv6hdr *hdr6 = ipv6_hdr(skb); skb->protocol = htons(ETH_P_IPV6); hdr6->hop_limit = dec.ttl; + success = true; + break; } - else - /* version 0 and version 1 are used by pseudo wires */ - success = false; + case MPT_UNSPEC: + break; + } + return success; } @@ -139,6 +226,7 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, struct net *net = dev_net(dev); struct mpls_shim_hdr *hdr; struct mpls_route *rt; + struct mpls_nh *nh; struct mpls_entry_decoded dec; struct net_device *out_dev; struct mpls_dev *mdev; @@ -176,8 +264,12 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, if (!rt) goto drop; + nh = mpls_select_multipath(rt, skb, dec.bos); + if (!nh) + goto drop; + /* Find the output device */ - out_dev = rcu_dereference(rt->rt_dev); + out_dev = rcu_dereference(nh->nh_dev); if (!mpls_output_possible(out_dev)) goto drop; @@ -192,7 +284,7 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, dec.ttl -= 1; /* Verify the destination can hold the packet */ - new_header_size = mpls_rt_header_size(rt); + new_header_size = mpls_nh_header_size(nh); mtu = mpls_dev_mtu(out_dev); if (mpls_pkt_too_big(skb, mtu - new_header_size)) goto drop; @@ -220,13 +312,20 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, /* Push the new labels */ hdr = mpls_hdr(skb); bos = dec.bos; - for (i = rt->rt_labels - 1; i >= 0; i--) { - hdr[i] = mpls_entry_encode(rt->rt_label[i], dec.ttl, 0, bos); + for (i = nh->nh_labels - 1; i >= 0; i--) { + hdr[i] = mpls_entry_encode(nh->nh_label[i], + dec.ttl, 0, bos); bos = false; } } - err = neigh_xmit(rt->rt_via_table, out_dev, rt->rt_via, skb); + /* If via wasn't specified then send out using device address */ + if (nh->nh_via_table == MPLS_NEIGH_TABLE_UNSPEC) + err = neigh_xmit(NEIGH_LINK_TABLE, out_dev, + out_dev->dev_addr, skb); + else + err = neigh_xmit(nh->nh_via_table, out_dev, + mpls_nh_via(rt, nh), skb); if (err) net_dbg_ratelimited("%s: packet transmission failed: %d\n", __func__, err); @@ -248,25 +347,35 @@ static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = { }; struct mpls_route_config { - u32 rc_protocol; - u32 rc_ifindex; - u16 rc_via_table; - u16 rc_via_alen; - u8 rc_via[MAX_VIA_ALEN]; - u32 rc_label; - u32 rc_output_labels; - u32 rc_output_label[MAX_NEW_LABELS]; - u32 rc_nlflags; - struct nl_info rc_nlinfo; + u32 rc_protocol; + u32 rc_ifindex; + u8 rc_via_table; + u8 rc_via_alen; + u8 rc_via[MAX_VIA_ALEN]; + u32 rc_label; + u8 rc_output_labels; + u32 rc_output_label[MAX_NEW_LABELS]; + u32 rc_nlflags; + enum mpls_payload_type rc_payload_type; + struct nl_info rc_nlinfo; + struct rtnexthop *rc_mp; + int rc_mp_len; }; -static struct mpls_route *mpls_rt_alloc(size_t alen) +static struct mpls_route *mpls_rt_alloc(int num_nh, u8 max_alen) { + u8 max_alen_aligned = ALIGN(max_alen, VIA_ALEN_ALIGN); struct mpls_route *rt; - rt = kzalloc(sizeof(*rt) + alen, GFP_KERNEL); - if (rt) - rt->rt_via_alen = alen; + rt = kzalloc(ALIGN(sizeof(*rt) + num_nh * sizeof(*rt->rt_nh), + VIA_ALEN_ALIGN) + + num_nh * max_alen_aligned, + GFP_KERNEL); + if (rt) { + rt->rt_nhn = num_nh; + rt->rt_max_alen = max_alen_aligned; + } + return rt; } @@ -286,30 +395,27 @@ static void mpls_notify_route(struct net *net, unsigned index, struct mpls_route *rt = new ? new : old; unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0; /* Ignore reserved labels for now */ - if (rt && (index >= 16)) + if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED)) rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags); } static void mpls_route_update(struct net *net, unsigned index, - struct net_device *dev, struct mpls_route *new, + struct mpls_route *new, const struct nl_info *info) { struct mpls_route __rcu **platform_label; - struct mpls_route *rt, *old = NULL; + struct mpls_route *rt; ASSERT_RTNL(); platform_label = rtnl_dereference(net->mpls.platform_label); rt = rtnl_dereference(platform_label[index]); - if (!dev || (rt && (rtnl_dereference(rt->rt_dev) == dev))) { - rcu_assign_pointer(platform_label[index], new); - old = rt; - } + rcu_assign_pointer(platform_label[index], new); - mpls_notify_route(net, index, old, new, info); + mpls_notify_route(net, index, rt, new, info); /* If we removed a route free it now */ - mpls_rt_free(old); + mpls_rt_free(rt); } static unsigned find_free_label(struct net *net) @@ -320,22 +426,300 @@ static unsigned find_free_label(struct net *net) platform_label = rtnl_dereference(net->mpls.platform_label); platform_labels = net->mpls.platform_labels; - for (index = 16; index < platform_labels; index++) { + for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels; + index++) { if (!rtnl_dereference(platform_label[index])) return index; } return LABEL_NOT_SPECIFIED; } +#if IS_ENABLED(CONFIG_INET) +static struct net_device *inet_fib_lookup_dev(struct net *net, + const void *addr) +{ + struct net_device *dev; + struct rtable *rt; + struct in_addr daddr; + + memcpy(&daddr, addr, sizeof(struct in_addr)); + rt = ip_route_output(net, daddr.s_addr, 0, 0, 0); + if (IS_ERR(rt)) + return ERR_CAST(rt); + + dev = rt->dst.dev; + dev_hold(dev); + + ip_rt_put(rt); + + return dev; +} +#else +static struct net_device *inet_fib_lookup_dev(struct net *net, + const void *addr) +{ + return ERR_PTR(-EAFNOSUPPORT); +} +#endif + +#if IS_ENABLED(CONFIG_IPV6) +static struct net_device *inet6_fib_lookup_dev(struct net *net, + const void *addr) +{ + struct net_device *dev; + struct dst_entry *dst; + struct flowi6 fl6; + int err; + + if (!ipv6_stub) + return ERR_PTR(-EAFNOSUPPORT); + + memset(&fl6, 0, sizeof(fl6)); + memcpy(&fl6.daddr, addr, sizeof(struct in6_addr)); + err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6); + if (err) + return ERR_PTR(err); + + dev = dst->dev; + dev_hold(dev); + dst_release(dst); + + return dev; +} +#else +static struct net_device *inet6_fib_lookup_dev(struct net *net, + const void *addr) +{ + return ERR_PTR(-EAFNOSUPPORT); +} +#endif + +static struct net_device *find_outdev(struct net *net, + struct mpls_route *rt, + struct mpls_nh *nh, int oif) +{ + struct net_device *dev = NULL; + + if (!oif) { + switch (nh->nh_via_table) { + case NEIGH_ARP_TABLE: + dev = inet_fib_lookup_dev(net, mpls_nh_via(rt, nh)); + break; + case NEIGH_ND_TABLE: + dev = inet6_fib_lookup_dev(net, mpls_nh_via(rt, nh)); + break; + case NEIGH_LINK_TABLE: + break; + } + } else { + dev = dev_get_by_index(net, oif); + } + + if (!dev) + return ERR_PTR(-ENODEV); + + /* The caller is holding rtnl anyways, so release the dev reference */ + dev_put(dev); + + return dev; +} + +static int mpls_nh_assign_dev(struct net *net, struct mpls_route *rt, + struct mpls_nh *nh, int oif) +{ + struct net_device *dev = NULL; + int err = -ENODEV; + + dev = find_outdev(net, rt, nh, oif); + if (IS_ERR(dev)) { + err = PTR_ERR(dev); + dev = NULL; + goto errout; + } + + /* Ensure this is a supported device */ + err = -EINVAL; + if (!mpls_dev_get(dev)) + goto errout; + + if ((nh->nh_via_table == NEIGH_LINK_TABLE) && + (dev->addr_len != nh->nh_via_alen)) + goto errout; + + RCU_INIT_POINTER(nh->nh_dev, dev); + + return 0; + +errout: + return err; +} + +static int mpls_nh_build_from_cfg(struct mpls_route_config *cfg, + struct mpls_route *rt) +{ + struct net *net = cfg->rc_nlinfo.nl_net; + struct mpls_nh *nh = rt->rt_nh; + int err; + int i; + + if (!nh) + return -ENOMEM; + + err = -EINVAL; + /* Ensure only a supported number of labels are present */ + if (cfg->rc_output_labels > MAX_NEW_LABELS) + goto errout; + + nh->nh_labels = cfg->rc_output_labels; + for (i = 0; i < nh->nh_labels; i++) + nh->nh_label[i] = cfg->rc_output_label[i]; + + nh->nh_via_table = cfg->rc_via_table; + memcpy(__mpls_nh_via(rt, nh), cfg->rc_via, cfg->rc_via_alen); + nh->nh_via_alen = cfg->rc_via_alen; + + err = mpls_nh_assign_dev(net, rt, nh, cfg->rc_ifindex); + if (err) + goto errout; + + return 0; + +errout: + return err; +} + +static int mpls_nh_build(struct net *net, struct mpls_route *rt, + struct mpls_nh *nh, int oif, + struct nlattr *via, struct nlattr *newdst) +{ + int err = -ENOMEM; + + if (!nh) + goto errout; + + if (newdst) { + err = nla_get_labels(newdst, MAX_NEW_LABELS, + &nh->nh_labels, nh->nh_label); + if (err) + goto errout; + } + + if (via) { + err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table, + __mpls_nh_via(rt, nh)); + if (err) + goto errout; + } else { + nh->nh_via_table = MPLS_NEIGH_TABLE_UNSPEC; + } + + err = mpls_nh_assign_dev(net, rt, nh, oif); + if (err) + goto errout; + + return 0; + +errout: + return err; +} + +static int mpls_count_nexthops(struct rtnexthop *rtnh, int len, + u8 cfg_via_alen, u8 *max_via_alen) +{ + int nhs = 0; + int remaining = len; + + if (!rtnh) { + *max_via_alen = cfg_via_alen; + return 1; + } + + *max_via_alen = 0; + + while (rtnh_ok(rtnh, remaining)) { + struct nlattr *nla, *attrs = rtnh_attrs(rtnh); + int attrlen; + + attrlen = rtnh_attrlen(rtnh); + nla = nla_find(attrs, attrlen, RTA_VIA); + if (nla && nla_len(nla) >= + offsetof(struct rtvia, rtvia_addr)) { + int via_alen = nla_len(nla) - + offsetof(struct rtvia, rtvia_addr); + + if (via_alen <= MAX_VIA_ALEN) + *max_via_alen = max_t(u16, *max_via_alen, + via_alen); + } + + nhs++; + rtnh = rtnh_next(rtnh, &remaining); + } + + /* leftover implies invalid nexthop configuration, discard it */ + return remaining > 0 ? 0 : nhs; +} + +static int mpls_nh_build_multi(struct mpls_route_config *cfg, + struct mpls_route *rt) +{ + struct rtnexthop *rtnh = cfg->rc_mp; + struct nlattr *nla_via, *nla_newdst; + int remaining = cfg->rc_mp_len; + int nhs = 0; + int err = 0; + + change_nexthops(rt) { + int attrlen; + + nla_via = NULL; + nla_newdst = NULL; + + err = -EINVAL; + if (!rtnh_ok(rtnh, remaining)) + goto errout; + + /* neither weighted multipath nor any flags + * are supported + */ + if (rtnh->rtnh_hops || rtnh->rtnh_flags) + goto errout; + + attrlen = rtnh_attrlen(rtnh); + if (attrlen > 0) { + struct nlattr *attrs = rtnh_attrs(rtnh); + + nla_via = nla_find(attrs, attrlen, RTA_VIA); + nla_newdst = nla_find(attrs, attrlen, RTA_NEWDST); + } + + err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh, + rtnh->rtnh_ifindex, nla_via, + nla_newdst); + if (err) + goto errout; + + rtnh = rtnh_next(rtnh, &remaining); + nhs++; + } endfor_nexthops(rt); + + rt->rt_nhn = nhs; + + return 0; + +errout: + return err; +} + static int mpls_route_add(struct mpls_route_config *cfg) { struct mpls_route __rcu **platform_label; struct net *net = cfg->rc_nlinfo.nl_net; - struct net_device *dev = NULL; struct mpls_route *rt, *old; - unsigned index; - int i; int err = -EINVAL; + u8 max_via_alen; + unsigned index; + int nhs; index = cfg->rc_label; @@ -345,33 +729,14 @@ static int mpls_route_add(struct mpls_route_config *cfg) index = find_free_label(net); } - /* The first 16 labels are reserved, and may not be set */ - if (index < 16) + /* Reserved labels may not be set */ + if (index < MPLS_LABEL_FIRST_UNRESERVED) goto errout; /* The full 20 bit range may not be supported. */ if (index >= net->mpls.platform_labels) goto errout; - /* Ensure only a supported number of labels are present */ - if (cfg->rc_output_labels > MAX_NEW_LABELS) - goto errout; - - err = -ENODEV; - dev = dev_get_by_index(net, cfg->rc_ifindex); - if (!dev) - goto errout; - - /* Ensure this is a supported device */ - err = -EINVAL; - if (!mpls_dev_get(dev)) - goto errout; - - err = -EINVAL; - if ((cfg->rc_via_table == NEIGH_LINK_TABLE) && - (dev->addr_len != cfg->rc_via_alen)) - goto errout; - /* Append makes no sense with mpls */ err = -EOPNOTSUPP; if (cfg->rc_nlflags & NLM_F_APPEND) @@ -391,27 +756,34 @@ static int mpls_route_add(struct mpls_route_config *cfg) if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old) goto errout; + err = -EINVAL; + nhs = mpls_count_nexthops(cfg->rc_mp, cfg->rc_mp_len, + cfg->rc_via_alen, &max_via_alen); + if (nhs == 0) + goto errout; + err = -ENOMEM; - rt = mpls_rt_alloc(cfg->rc_via_alen); + rt = mpls_rt_alloc(nhs, max_via_alen); if (!rt) goto errout; - rt->rt_labels = cfg->rc_output_labels; - for (i = 0; i < rt->rt_labels; i++) - rt->rt_label[i] = cfg->rc_output_label[i]; rt->rt_protocol = cfg->rc_protocol; - RCU_INIT_POINTER(rt->rt_dev, dev); - rt->rt_via_table = cfg->rc_via_table; - memcpy(rt->rt_via, cfg->rc_via, cfg->rc_via_alen); + rt->rt_payload_type = cfg->rc_payload_type; - mpls_route_update(net, index, NULL, rt, &cfg->rc_nlinfo); + if (cfg->rc_mp) + err = mpls_nh_build_multi(cfg, rt); + else + err = mpls_nh_build_from_cfg(cfg, rt); + if (err) + goto freert; + + mpls_route_update(net, index, rt, &cfg->rc_nlinfo); - dev_put(dev); return 0; +freert: + mpls_rt_free(rt); errout: - if (dev) - dev_put(dev); return err; } @@ -423,15 +795,15 @@ static int mpls_route_del(struct mpls_route_config *cfg) index = cfg->rc_label; - /* The first 16 labels are reserved, and may not be removed */ - if (index < 16) + /* Reserved labels may not be removed */ + if (index < MPLS_LABEL_FIRST_UNRESERVED) goto errout; /* The full 20 bit range may not be supported */ if (index >= net->mpls.platform_labels) goto errout; - mpls_route_update(net, index, NULL, NULL, &cfg->rc_nlinfo); + mpls_route_update(net, index, NULL, &cfg->rc_nlinfo); err = 0; errout: @@ -528,9 +900,11 @@ static void mpls_ifdown(struct net_device *dev) struct mpls_route *rt = rtnl_dereference(platform_label[index]); if (!rt) continue; - if (rtnl_dereference(rt->rt_dev) != dev) - continue; - rt->rt_dev = NULL; + for_nexthops(rt) { + if (rtnl_dereference(nh->nh_dev) != dev) + continue; + nh->nh_dev = NULL; + } endfor_nexthops(rt); } mdev = mpls_dev_get(dev); @@ -626,9 +1000,10 @@ int nla_put_labels(struct sk_buff *skb, int attrtype, return 0; } +EXPORT_SYMBOL_GPL(nla_put_labels); int nla_get_labels(const struct nlattr *nla, - u32 max_labels, u32 *labels, u32 label[]) + u32 max_labels, u8 *labels, u32 label[]) { unsigned len = nla_len(nla); unsigned nla_labels; @@ -671,6 +1046,49 @@ int nla_get_labels(const struct nlattr *nla, *labels = nla_labels; return 0; } +EXPORT_SYMBOL_GPL(nla_get_labels); + +int nla_get_via(const struct nlattr *nla, u8 *via_alen, + u8 *via_table, u8 via_addr[]) +{ + struct rtvia *via = nla_data(nla); + int err = -EINVAL; + int alen; + + if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) + goto errout; + alen = nla_len(nla) - + offsetof(struct rtvia, rtvia_addr); + if (alen > MAX_VIA_ALEN) + goto errout; + + /* Validate the address family */ + switch (via->rtvia_family) { + case AF_PACKET: + *via_table = NEIGH_LINK_TABLE; + break; + case AF_INET: + *via_table = NEIGH_ARP_TABLE; + if (alen != 4) + goto errout; + break; + case AF_INET6: + *via_table = NEIGH_ND_TABLE; + if (alen != 16) + goto errout; + break; + default: + /* Unsupported address family */ + goto errout; + } + + memcpy(via_addr, via->rtvia_addr, alen); + *via_alen = alen; + err = 0; + +errout: + return err; +} static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, struct mpls_route_config *cfg) @@ -713,6 +1131,7 @@ static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, cfg->rc_label = LABEL_NOT_SPECIFIED; cfg->rc_protocol = rtm->rtm_protocol; + cfg->rc_via_table = MPLS_NEIGH_TABLE_UNSPEC; cfg->rc_nlflags = nlh->nlmsg_flags; cfg->rc_nlinfo.portid = NETLINK_CB(skb).portid; cfg->rc_nlinfo.nlh = nlh; @@ -735,48 +1154,28 @@ static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, break; case RTA_DST: { - u32 label_count; + u8 label_count; if (nla_get_labels(nla, 1, &label_count, &cfg->rc_label)) goto errout; - /* The first 16 labels are reserved, and may not be set */ - if (cfg->rc_label < 16) + /* Reserved labels may not be set */ + if (cfg->rc_label < MPLS_LABEL_FIRST_UNRESERVED) goto errout; break; } case RTA_VIA: { - struct rtvia *via = nla_data(nla); - if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) - goto errout; - cfg->rc_via_alen = nla_len(nla) - - offsetof(struct rtvia, rtvia_addr); - if (cfg->rc_via_alen > MAX_VIA_ALEN) - goto errout; - - /* Validate the address family */ - switch(via->rtvia_family) { - case AF_PACKET: - cfg->rc_via_table = NEIGH_LINK_TABLE; - break; - case AF_INET: - cfg->rc_via_table = NEIGH_ARP_TABLE; - if (cfg->rc_via_alen != 4) - goto errout; - break; - case AF_INET6: - cfg->rc_via_table = NEIGH_ND_TABLE; - if (cfg->rc_via_alen != 16) - goto errout; - break; - default: - /* Unsupported address family */ + if (nla_get_via(nla, &cfg->rc_via_alen, + &cfg->rc_via_table, cfg->rc_via)) goto errout; - } - - memcpy(cfg->rc_via, via->rtvia_addr, cfg->rc_via_alen); + break; + } + case RTA_MULTIPATH: + { + cfg->rc_mp = nla_data(nla); + cfg->rc_mp_len = nla_len(nla); break; } default: @@ -837,16 +1236,54 @@ static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event, rtm->rtm_type = RTN_UNICAST; rtm->rtm_flags = 0; - if (rt->rt_labels && - nla_put_labels(skb, RTA_NEWDST, rt->rt_labels, rt->rt_label)) - goto nla_put_failure; - if (nla_put_via(skb, rt->rt_via_table, rt->rt_via, rt->rt_via_alen)) - goto nla_put_failure; - dev = rtnl_dereference(rt->rt_dev); - if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex)) - goto nla_put_failure; if (nla_put_labels(skb, RTA_DST, 1, &label)) goto nla_put_failure; + if (rt->rt_nhn == 1) { + const struct mpls_nh *nh = rt->rt_nh; + + if (nh->nh_labels && + nla_put_labels(skb, RTA_NEWDST, nh->nh_labels, + nh->nh_label)) + goto nla_put_failure; + if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && + nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh), + nh->nh_via_alen)) + goto nla_put_failure; + dev = rtnl_dereference(nh->nh_dev); + if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex)) + goto nla_put_failure; + } else { + struct rtnexthop *rtnh; + struct nlattr *mp; + + mp = nla_nest_start(skb, RTA_MULTIPATH); + if (!mp) + goto nla_put_failure; + + for_nexthops(rt) { + rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); + if (!rtnh) + goto nla_put_failure; + + dev = rtnl_dereference(nh->nh_dev); + if (dev) + rtnh->rtnh_ifindex = dev->ifindex; + if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST, + nh->nh_labels, + nh->nh_label)) + goto nla_put_failure; + if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && + nla_put_via(skb, nh->nh_via_table, + mpls_nh_via(rt, nh), + nh->nh_via_alen)) + goto nla_put_failure; + + /* length of rtnetlink header + attributes */ + rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh; + } endfor_nexthops(rt); + + nla_nest_end(skb, mp); + } nlmsg_end(skb, nlh); return 0; @@ -866,8 +1303,8 @@ static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb) ASSERT_RTNL(); index = cb->args[0]; - if (index < 16) - index = 16; + if (index < MPLS_LABEL_FIRST_UNRESERVED) + index = MPLS_LABEL_FIRST_UNRESERVED; platform_label = rtnl_dereference(net->mpls.platform_label); platform_labels = net->mpls.platform_labels; @@ -891,12 +1328,33 @@ static inline size_t lfib_nlmsg_size(struct mpls_route *rt) { size_t payload = NLMSG_ALIGN(sizeof(struct rtmsg)) - + nla_total_size(2 + rt->rt_via_alen) /* RTA_VIA */ + nla_total_size(4); /* RTA_DST */ - if (rt->rt_labels) /* RTA_NEWDST */ - payload += nla_total_size(rt->rt_labels * 4); - if (rt->rt_dev) /* RTA_OIF */ - payload += nla_total_size(4); + + if (rt->rt_nhn == 1) { + struct mpls_nh *nh = rt->rt_nh; + + if (nh->nh_dev) + payload += nla_total_size(4); /* RTA_OIF */ + if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) /* RTA_VIA */ + payload += nla_total_size(2 + nh->nh_via_alen); + if (nh->nh_labels) /* RTA_NEWDST */ + payload += nla_total_size(nh->nh_labels * 4); + } else { + /* each nexthop is packed in an attribute */ + size_t nhsize = 0; + + for_nexthops(rt) { + nhsize += nla_total_size(sizeof(struct rtnexthop)); + /* RTA_VIA */ + if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) + nhsize += nla_total_size(2 + nh->nh_via_alen); + if (nh->nh_labels) + nhsize += nla_total_size(nh->nh_labels * 4); + } endfor_nexthops(rt); + /* nested attribute */ + payload += nla_total_size(nhsize); + } + return payload; } @@ -948,23 +1406,29 @@ static int resize_platform_label_table(struct net *net, size_t limit) /* In case the predefined labels need to be populated */ if (limit > MPLS_LABEL_IPV4NULL) { struct net_device *lo = net->loopback_dev; - rt0 = mpls_rt_alloc(lo->addr_len); + rt0 = mpls_rt_alloc(1, lo->addr_len); if (!rt0) goto nort0; - RCU_INIT_POINTER(rt0->rt_dev, lo); + RCU_INIT_POINTER(rt0->rt_nh->nh_dev, lo); rt0->rt_protocol = RTPROT_KERNEL; - rt0->rt_via_table = NEIGH_LINK_TABLE; - memcpy(rt0->rt_via, lo->dev_addr, lo->addr_len); + rt0->rt_payload_type = MPT_IPV4; + rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE; + rt0->rt_nh->nh_via_alen = lo->addr_len; + memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr, + lo->addr_len); } if (limit > MPLS_LABEL_IPV6NULL) { struct net_device *lo = net->loopback_dev; - rt2 = mpls_rt_alloc(lo->addr_len); + rt2 = mpls_rt_alloc(1, lo->addr_len); if (!rt2) goto nort2; - RCU_INIT_POINTER(rt2->rt_dev, lo); + RCU_INIT_POINTER(rt2->rt_nh->nh_dev, lo); rt2->rt_protocol = RTPROT_KERNEL; - rt2->rt_via_table = NEIGH_LINK_TABLE; - memcpy(rt2->rt_via, lo->dev_addr, lo->addr_len); + rt2->rt_payload_type = MPT_IPV6; + rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE; + rt2->rt_nh->nh_via_alen = lo->addr_len; + memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr, + lo->addr_len); } rtnl_lock(); @@ -974,7 +1438,7 @@ static int resize_platform_label_table(struct net *net, size_t limit) /* Free any labels beyond the new table */ for (index = limit; index < old_limit; index++) - mpls_route_update(net, index, NULL, NULL, NULL); + mpls_route_update(net, index, NULL, NULL); /* Copy over the old labels */ cp_size = size; @@ -1066,8 +1530,10 @@ static int mpls_net_init(struct net *net) table[0].data = net; net->mpls.ctl = register_net_sysctl(net, "net/mpls", table); - if (net->mpls.ctl == NULL) + if (net->mpls.ctl == NULL) { + kfree(table); return -ENOMEM; + } return 0; } diff --git a/kernel/net/mpls/internal.h b/kernel/net/mpls/internal.h index 8cabeb5a1..bde52ce88 100644 --- a/kernel/net/mpls/internal.h +++ b/kernel/net/mpls/internal.h @@ -21,6 +21,76 @@ struct mpls_dev { struct sk_buff; +#define LABEL_NOT_SPECIFIED (1 << 20) +#define MAX_NEW_LABELS 2 + +/* This maximum ha length copied from the definition of struct neighbour */ +#define VIA_ALEN_ALIGN sizeof(unsigned long) +#define MAX_VIA_ALEN (ALIGN(MAX_ADDR_LEN, VIA_ALEN_ALIGN)) + +enum mpls_payload_type { + MPT_UNSPEC, /* IPv4 or IPv6 */ + MPT_IPV4 = 4, + MPT_IPV6 = 6, + + /* Other types not implemented: + * - Pseudo-wire with or without control word (RFC4385) + * - GAL (RFC5586) + */ +}; + +struct mpls_nh { /* next hop label forwarding entry */ + struct net_device __rcu *nh_dev; + u32 nh_label[MAX_NEW_LABELS]; + u8 nh_labels; + u8 nh_via_alen; + u8 nh_via_table; +}; + +/* The route, nexthops and vias are stored together in the same memory + * block: + * + * +----------------------+ + * | mpls_route | + * +----------------------+ + * | mpls_nh 0 | + * +----------------------+ + * | ... | + * +----------------------+ + * | mpls_nh n-1 | + * +----------------------+ + * | alignment padding | + * +----------------------+ + * | via[rt_max_alen] 0 | + * +----------------------+ + * | ... | + * +----------------------+ + * | via[rt_max_alen] n-1 | + * +----------------------+ + */ +struct mpls_route { /* next hop label forwarding entry */ + struct rcu_head rt_rcu; + u8 rt_protocol; + u8 rt_payload_type; + u8 rt_max_alen; + unsigned int rt_nhn; + struct mpls_nh rt_nh[0]; +}; + +#define for_nexthops(rt) { \ + int nhsel; struct mpls_nh *nh; \ + for (nhsel = 0, nh = (rt)->rt_nh; \ + nhsel < (rt)->rt_nhn; \ + nh++, nhsel++) + +#define change_nexthops(rt) { \ + int nhsel; struct mpls_nh *nh; \ + for (nhsel = 0, nh = (struct mpls_nh *)((rt)->rt_nh); \ + nhsel < (rt)->rt_nhn; \ + nh++, nhsel++) + +#define endfor_nexthops(rt) } + static inline struct mpls_shim_hdr *mpls_hdr(const struct sk_buff *skb) { return (struct mpls_shim_hdr *)skb_network_header(skb); @@ -50,7 +120,14 @@ static inline struct mpls_entry_decoded mpls_entry_decode(struct mpls_shim_hdr * return result; } -int nla_put_labels(struct sk_buff *skb, int attrtype, u8 labels, const u32 label[]); -int nla_get_labels(const struct nlattr *nla, u32 max_labels, u32 *labels, u32 label[]); +int nla_put_labels(struct sk_buff *skb, int attrtype, u8 labels, + const u32 label[]); +int nla_get_labels(const struct nlattr *nla, u32 max_labels, u8 *labels, + u32 label[]); +int nla_get_via(const struct nlattr *nla, u8 *via_alen, u8 *via_table, + u8 via[]); +bool mpls_output_possible(const struct net_device *dev); +unsigned int mpls_dev_mtu(const struct net_device *dev); +bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu); #endif /* MPLS_INTERNAL_H */ diff --git a/kernel/net/mpls/mpls_gso.c b/kernel/net/mpls/mpls_gso.c index 809df534a..0183b32da 100644 --- a/kernel/net/mpls/mpls_gso.c +++ b/kernel/net/mpls/mpls_gso.c @@ -62,6 +62,7 @@ out: static struct packet_offload mpls_mc_offload __read_mostly = { .type = cpu_to_be16(ETH_P_MPLS_MC), + .priority = 15, .callbacks = { .gso_segment = mpls_gso_segment, }, @@ -69,6 +70,7 @@ static struct packet_offload mpls_mc_offload __read_mostly = { static struct packet_offload mpls_uc_offload __read_mostly = { .type = cpu_to_be16(ETH_P_MPLS_UC), + .priority = 15, .callbacks = { .gso_segment = mpls_gso_segment, }, diff --git a/kernel/net/mpls/mpls_iptunnel.c b/kernel/net/mpls/mpls_iptunnel.c new file mode 100644 index 000000000..64afd3d0b --- /dev/null +++ b/kernel/net/mpls/mpls_iptunnel.c @@ -0,0 +1,231 @@ +/* + * mpls tunnels An implementation mpls tunnels using the light weight tunnel + * infrastructure + * + * Authors: Roopa Prabhu, <roopa@cumulusnetworks.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ +#include <linux/types.h> +#include <linux/skbuff.h> +#include <linux/net.h> +#include <linux/module.h> +#include <linux/mpls.h> +#include <linux/vmalloc.h> +#include <net/ip.h> +#include <net/dst.h> +#include <net/lwtunnel.h> +#include <net/netevent.h> +#include <net/netns/generic.h> +#include <net/ip6_fib.h> +#include <net/route.h> +#include <net/mpls_iptunnel.h> +#include <linux/mpls_iptunnel.h> +#include "internal.h" + +static const struct nla_policy mpls_iptunnel_policy[MPLS_IPTUNNEL_MAX + 1] = { + [MPLS_IPTUNNEL_DST] = { .type = NLA_U32 }, +}; + +static unsigned int mpls_encap_size(struct mpls_iptunnel_encap *en) +{ + /* The size of the layer 2.5 labels to be added for this route */ + return en->labels * sizeof(struct mpls_shim_hdr); +} + +int mpls_output(struct net *net, struct sock *sk, struct sk_buff *skb) +{ + struct mpls_iptunnel_encap *tun_encap_info; + struct mpls_shim_hdr *hdr; + struct net_device *out_dev; + unsigned int hh_len; + unsigned int new_header_size; + unsigned int mtu; + struct dst_entry *dst = skb_dst(skb); + struct rtable *rt = NULL; + struct rt6_info *rt6 = NULL; + int err = 0; + bool bos; + int i; + unsigned int ttl; + + /* Obtain the ttl */ + if (dst->ops->family == AF_INET) { + ttl = ip_hdr(skb)->ttl; + rt = (struct rtable *)dst; + } else if (dst->ops->family == AF_INET6) { + ttl = ipv6_hdr(skb)->hop_limit; + rt6 = (struct rt6_info *)dst; + } else { + goto drop; + } + + skb_orphan(skb); + + /* Find the output device */ + out_dev = dst->dev; + if (!mpls_output_possible(out_dev) || + !dst->lwtstate || skb_warn_if_lro(skb)) + goto drop; + + skb_forward_csum(skb); + + tun_encap_info = mpls_lwtunnel_encap(dst->lwtstate); + + /* Verify the destination can hold the packet */ + new_header_size = mpls_encap_size(tun_encap_info); + mtu = mpls_dev_mtu(out_dev); + if (mpls_pkt_too_big(skb, mtu - new_header_size)) + goto drop; + + hh_len = LL_RESERVED_SPACE(out_dev); + if (!out_dev->header_ops) + hh_len = 0; + + /* Ensure there is enough space for the headers in the skb */ + if (skb_cow(skb, hh_len + new_header_size)) + goto drop; + + skb_push(skb, new_header_size); + skb_reset_network_header(skb); + + skb->dev = out_dev; + skb->protocol = htons(ETH_P_MPLS_UC); + + /* Push the new labels */ + hdr = mpls_hdr(skb); + bos = true; + for (i = tun_encap_info->labels - 1; i >= 0; i--) { + hdr[i] = mpls_entry_encode(tun_encap_info->label[i], + ttl, 0, bos); + bos = false; + } + + if (rt) + err = neigh_xmit(NEIGH_ARP_TABLE, out_dev, &rt->rt_gateway, + skb); + else if (rt6) + err = neigh_xmit(NEIGH_ND_TABLE, out_dev, &rt6->rt6i_gateway, + skb); + if (err) + net_dbg_ratelimited("%s: packet transmission failed: %d\n", + __func__, err); + + return 0; + +drop: + kfree_skb(skb); + return -EINVAL; +} + +static int mpls_build_state(struct net_device *dev, struct nlattr *nla, + unsigned int family, const void *cfg, + struct lwtunnel_state **ts) +{ + struct mpls_iptunnel_encap *tun_encap_info; + struct nlattr *tb[MPLS_IPTUNNEL_MAX + 1]; + struct lwtunnel_state *newts; + int tun_encap_info_len; + int ret; + + ret = nla_parse_nested(tb, MPLS_IPTUNNEL_MAX, nla, + mpls_iptunnel_policy); + if (ret < 0) + return ret; + + if (!tb[MPLS_IPTUNNEL_DST]) + return -EINVAL; + + tun_encap_info_len = sizeof(*tun_encap_info); + + newts = lwtunnel_state_alloc(tun_encap_info_len); + if (!newts) + return -ENOMEM; + + newts->len = tun_encap_info_len; + tun_encap_info = mpls_lwtunnel_encap(newts); + ret = nla_get_labels(tb[MPLS_IPTUNNEL_DST], MAX_NEW_LABELS, + &tun_encap_info->labels, tun_encap_info->label); + if (ret) + goto errout; + newts->type = LWTUNNEL_ENCAP_MPLS; + newts->flags |= LWTUNNEL_STATE_OUTPUT_REDIRECT; + + *ts = newts; + + return 0; + +errout: + kfree(newts); + *ts = NULL; + + return ret; +} + +static int mpls_fill_encap_info(struct sk_buff *skb, + struct lwtunnel_state *lwtstate) +{ + struct mpls_iptunnel_encap *tun_encap_info; + + tun_encap_info = mpls_lwtunnel_encap(lwtstate); + + if (nla_put_labels(skb, MPLS_IPTUNNEL_DST, tun_encap_info->labels, + tun_encap_info->label)) + goto nla_put_failure; + + return 0; + +nla_put_failure: + return -EMSGSIZE; +} + +static int mpls_encap_nlsize(struct lwtunnel_state *lwtstate) +{ + struct mpls_iptunnel_encap *tun_encap_info; + + tun_encap_info = mpls_lwtunnel_encap(lwtstate); + + return nla_total_size(tun_encap_info->labels * 4); +} + +static int mpls_encap_cmp(struct lwtunnel_state *a, struct lwtunnel_state *b) +{ + struct mpls_iptunnel_encap *a_hdr = mpls_lwtunnel_encap(a); + struct mpls_iptunnel_encap *b_hdr = mpls_lwtunnel_encap(b); + int l; + + if (a_hdr->labels != b_hdr->labels) + return 1; + + for (l = 0; l < MAX_NEW_LABELS; l++) + if (a_hdr->label[l] != b_hdr->label[l]) + return 1; + return 0; +} + +static const struct lwtunnel_encap_ops mpls_iptun_ops = { + .build_state = mpls_build_state, + .output = mpls_output, + .fill_encap = mpls_fill_encap_info, + .get_encap_size = mpls_encap_nlsize, + .cmp_encap = mpls_encap_cmp, +}; + +static int __init mpls_iptunnel_init(void) +{ + return lwtunnel_encap_add_ops(&mpls_iptun_ops, LWTUNNEL_ENCAP_MPLS); +} +module_init(mpls_iptunnel_init); + +static void __exit mpls_iptunnel_exit(void) +{ + lwtunnel_encap_del_ops(&mpls_iptun_ops, LWTUNNEL_ENCAP_MPLS); +} +module_exit(mpls_iptunnel_exit); + +MODULE_DESCRIPTION("MultiProtocol Label Switching IP Tunnels"); +MODULE_LICENSE("GPL v2"); |