diff options
Diffstat (limited to 'net/mpls/af_mpls.c')
-rw-r--r-- | net/mpls/af_mpls.c | 496 |
1 files changed, 349 insertions, 147 deletions
diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c index bb185a28de98..ee3097a97185 100644 --- a/net/mpls/af_mpls.c +++ b/net/mpls/af_mpls.c @@ -19,37 +19,9 @@ #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))) - -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_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_payload_type; - u8 rt_labels; - u8 rt_via_alen; - u8 rt_via_table; - u8 rt_via[0]; -}; - static int zero = 0; static int label_limit = (1 << 20) - 1; @@ -80,10 +52,10 @@ bool mpls_output_possible(const struct net_device *dev) } EXPORT_SYMBOL_GPL(mpls_output_possible); -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); } unsigned int mpls_dev_mtu(const struct net_device *dev) @@ -105,6 +77,12 @@ bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu) } EXPORT_SYMBOL_GPL(mpls_pkt_too_big); +static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt) +{ + /* assume single nexthop for now */ + return &rt->rt_nh[0]; +} + static bool mpls_egress(struct mpls_route *rt, struct sk_buff *skb, struct mpls_entry_decoded dec) { @@ -159,6 +137,7 @@ 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; @@ -196,8 +175,12 @@ static int mpls_forward(struct sk_buff *skb, struct net_device *dev, if (!rt) goto drop; + nh = mpls_select_multipath(rt); + 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; @@ -212,7 +195,7 @@ 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; @@ -240,13 +223,14 @@ 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); + err = neigh_xmit(nh->nh_via_table, out_dev, nh->nh_via, skb); if (err) net_dbg_ratelimited("%s: packet transmission failed: %d\n", __func__, err); @@ -270,24 +254,28 @@ 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_table; + u8 rc_via_alen; u8 rc_via[MAX_VIA_ALEN]; u32 rc_label; - u32 rc_output_labels; + 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) { struct mpls_route *rt; - rt = kzalloc(sizeof(*rt) + alen, GFP_KERNEL); + rt = kzalloc(sizeof(*rt) + (num_nh * sizeof(struct mpls_nh)), + GFP_KERNEL); if (rt) - rt->rt_via_alen = alen; + rt->rt_nhn = num_nh; + return rt; } @@ -312,25 +300,22 @@ static void mpls_notify_route(struct net *net, unsigned index, } 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) @@ -406,40 +391,193 @@ static struct net_device *inet6_fib_lookup_dev(struct net *net, void *addr) #endif static struct net_device *find_outdev(struct net *net, - struct mpls_route_config *cfg) + struct mpls_nh *nh, int oif) { struct net_device *dev = NULL; - if (!cfg->rc_ifindex) { - switch (cfg->rc_via_table) { + if (!oif) { + switch (nh->nh_via_table) { case NEIGH_ARP_TABLE: - dev = inet_fib_lookup_dev(net, cfg->rc_via); + dev = inet_fib_lookup_dev(net, nh->nh_via); break; case NEIGH_ND_TABLE: - dev = inet6_fib_lookup_dev(net, cfg->rc_via); + dev = inet6_fib_lookup_dev(net, nh->nh_via); break; case NEIGH_LINK_TABLE: break; } } else { - dev = dev_get_by_index(net, cfg->rc_ifindex); + 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_nh *nh, int oif) +{ + struct net_device *dev = NULL; + int err = -ENODEV; + + dev = find_outdev(net, 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; + + 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(nh->nh_via, cfg->rc_via, cfg->rc_via_alen); + nh->nh_via_alen = cfg->rc_via_alen; + + err = mpls_nh_assign_dev(net, nh, cfg->rc_ifindex); + if (err) + goto errout; + + return 0; + +errout: + return err; +} + +static int mpls_nh_build(struct net *net, 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; + } + + err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table, + nh->nh_via); + if (err) + goto errout; + + err = mpls_nh_assign_dev(net, nh, oif); + if (err) + goto errout; + + return 0; + +errout: + return err; +} + +static int mpls_count_nexthops(struct rtnexthop *rtnh, int len) +{ + int nhs = 0; + int remaining = len; + + while (rtnh_ok(rtnh, remaining)) { + 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; + + 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); + } + + if (!nla_via) + goto errout; + + err = mpls_nh_build(cfg->rc_nlinfo.nl_net, 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; + unsigned index; + int nhs = 1; /* default to one nexthop */ index = cfg->rc_label; @@ -457,27 +595,6 @@ static int mpls_route_add(struct mpls_route_config *cfg) 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; - - dev = find_outdev(net, cfg); - 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; - - 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) @@ -497,28 +614,35 @@ static int mpls_route_add(struct mpls_route_config *cfg) if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old) goto errout; + if (cfg->rc_mp) { + err = -EINVAL; + nhs = mpls_count_nexthops(cfg->rc_mp, cfg->rc_mp_len); + if (nhs == 0) + goto errout; + } + err = -ENOMEM; - rt = mpls_rt_alloc(cfg->rc_via_alen); + rt = mpls_rt_alloc(nhs); 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_payload_type = cfg->rc_payload_type; - rt->rt_via_table = cfg->rc_via_table; - memcpy(rt->rt_via, cfg->rc_via, cfg->rc_via_alen); - 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; } @@ -538,7 +662,7 @@ static int mpls_route_del(struct mpls_route_config *cfg) 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: @@ -635,9 +759,11 @@ 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); @@ -736,7 +862,7 @@ int nla_put_labels(struct sk_buff *skb, int attrtype, 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; @@ -781,6 +907,48 @@ int nla_get_labels(const struct nlattr *nla, } 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) { @@ -844,7 +1012,7 @@ 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; @@ -857,35 +1025,15 @@ static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, } 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) + if (nla_get_via(nla, &cfg->rc_via_alen, + &cfg->rc_via_table, cfg->rc_via)) 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 */ - 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: @@ -946,16 +1094,52 @@ 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) { + 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 (nla_put_via(skb, nh->nh_via_table, nh->nh_via, + 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 (nla_put_via(skb, nh->nh_via_table, + nh->nh_via, + 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; @@ -1000,12 +1184,30 @@ 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 */ + payload += nla_total_size(2 + nh->nh_via_alen); /* RTA_VIA */ + 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)); + 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; } @@ -1057,25 +1259,25 @@ 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); 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_payload_type = MPT_IPV4; - rt0->rt_via_table = NEIGH_LINK_TABLE; - memcpy(rt0->rt_via, lo->dev_addr, lo->addr_len); + rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE; + memcpy(rt0->rt_nh->nh_via, 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); 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_payload_type = MPT_IPV6; - rt2->rt_via_table = NEIGH_LINK_TABLE; - memcpy(rt2->rt_via, lo->dev_addr, lo->addr_len); + rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE; + memcpy(rt2->rt_nh->nh_via, lo->dev_addr, lo->addr_len); } rtnl_lock(); @@ -1085,7 +1287,7 @@ 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; |