v4.19.13 snapshot.
diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c
new file mode 100644
index 0000000..60325db
--- /dev/null
+++ b/net/ipv6/seg6_local.c
@@ -0,0 +1,1114 @@
+/*
+ * SR-IPv6 implementation
+ *
+ * Authors:
+ * David Lebrun <david.lebrun@uclouvain.be>
+ * eBPF support: Mathieu Xhonneux <m.xhonneux@gmail.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 <net/ip.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/seg6.h>
+#include <linux/seg6.h>
+#include <linux/seg6_local.h>
+#include <net/addrconf.h>
+#include <net/ip6_route.h>
+#include <net/dst_cache.h>
+#ifdef CONFIG_IPV6_SEG6_HMAC
+#include <net/seg6_hmac.h>
+#endif
+#include <net/seg6_local.h>
+#include <linux/etherdevice.h>
+#include <linux/bpf.h>
+
+struct seg6_local_lwt;
+
+struct seg6_action_desc {
+ int action;
+ unsigned long attrs;
+ int (*input)(struct sk_buff *skb, struct seg6_local_lwt *slwt);
+ int static_headroom;
+};
+
+struct bpf_lwt_prog {
+ struct bpf_prog *prog;
+ char *name;
+};
+
+struct seg6_local_lwt {
+ int action;
+ struct ipv6_sr_hdr *srh;
+ int table;
+ struct in_addr nh4;
+ struct in6_addr nh6;
+ int iif;
+ int oif;
+ struct bpf_lwt_prog bpf;
+
+ int headroom;
+ struct seg6_action_desc *desc;
+};
+
+static struct seg6_local_lwt *seg6_local_lwtunnel(struct lwtunnel_state *lwt)
+{
+ return (struct seg6_local_lwt *)lwt->data;
+}
+
+static struct ipv6_sr_hdr *get_srh(struct sk_buff *skb)
+{
+ struct ipv6_sr_hdr *srh;
+ int len, srhoff = 0;
+
+ if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
+ return NULL;
+
+ if (!pskb_may_pull(skb, srhoff + sizeof(*srh)))
+ return NULL;
+
+ srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
+
+ len = (srh->hdrlen + 1) << 3;
+
+ if (!pskb_may_pull(skb, srhoff + len))
+ return NULL;
+
+ if (!seg6_validate_srh(srh, len))
+ return NULL;
+
+ return srh;
+}
+
+static struct ipv6_sr_hdr *get_and_validate_srh(struct sk_buff *skb)
+{
+ struct ipv6_sr_hdr *srh;
+
+ srh = get_srh(skb);
+ if (!srh)
+ return NULL;
+
+ if (srh->segments_left == 0)
+ return NULL;
+
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ if (!seg6_hmac_validate_skb(skb))
+ return NULL;
+#endif
+
+ return srh;
+}
+
+static bool decap_and_validate(struct sk_buff *skb, int proto)
+{
+ struct ipv6_sr_hdr *srh;
+ unsigned int off = 0;
+
+ srh = get_srh(skb);
+ if (srh && srh->segments_left > 0)
+ return false;
+
+#ifdef CONFIG_IPV6_SEG6_HMAC
+ if (srh && !seg6_hmac_validate_skb(skb))
+ return false;
+#endif
+
+ if (ipv6_find_hdr(skb, &off, proto, NULL, NULL) < 0)
+ return false;
+
+ if (!pskb_pull(skb, off))
+ return false;
+
+ skb_postpull_rcsum(skb, skb_network_header(skb), off);
+
+ skb_reset_network_header(skb);
+ skb_reset_transport_header(skb);
+ skb->encapsulation = 0;
+
+ return true;
+}
+
+static void advance_nextseg(struct ipv6_sr_hdr *srh, struct in6_addr *daddr)
+{
+ struct in6_addr *addr;
+
+ srh->segments_left--;
+ addr = srh->segments + srh->segments_left;
+ *daddr = *addr;
+}
+
+int seg6_lookup_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,
+ u32 tbl_id)
+{
+ struct net *net = dev_net(skb->dev);
+ struct ipv6hdr *hdr = ipv6_hdr(skb);
+ int flags = RT6_LOOKUP_F_HAS_SADDR;
+ struct dst_entry *dst = NULL;
+ struct rt6_info *rt;
+ struct flowi6 fl6;
+
+ fl6.flowi6_iif = skb->dev->ifindex;
+ fl6.daddr = nhaddr ? *nhaddr : hdr->daddr;
+ fl6.saddr = hdr->saddr;
+ fl6.flowlabel = ip6_flowinfo(hdr);
+ fl6.flowi6_mark = skb->mark;
+ fl6.flowi6_proto = hdr->nexthdr;
+
+ if (nhaddr)
+ fl6.flowi6_flags = FLOWI_FLAG_KNOWN_NH;
+
+ if (!tbl_id) {
+ dst = ip6_route_input_lookup(net, skb->dev, &fl6, skb, flags);
+ } else {
+ struct fib6_table *table;
+
+ table = fib6_get_table(net, tbl_id);
+ if (!table)
+ goto out;
+
+ rt = ip6_pol_route(net, table, 0, &fl6, skb, flags);
+ dst = &rt->dst;
+ }
+
+ if (dst && dst->dev->flags & IFF_LOOPBACK && !dst->error) {
+ dst_release(dst);
+ dst = NULL;
+ }
+
+out:
+ if (!dst) {
+ rt = net->ipv6.ip6_blk_hole_entry;
+ dst = &rt->dst;
+ dst_hold(dst);
+ }
+
+ skb_dst_drop(skb);
+ skb_dst_set(skb, dst);
+ return dst->error;
+}
+
+/* regular endpoint function */
+static int input_action_end(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ struct ipv6_sr_hdr *srh;
+
+ srh = get_and_validate_srh(skb);
+ if (!srh)
+ goto drop;
+
+ advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
+
+ seg6_lookup_nexthop(skb, NULL, 0);
+
+ return dst_input(skb);
+
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+/* regular endpoint, and forward to specified nexthop */
+static int input_action_end_x(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ struct ipv6_sr_hdr *srh;
+
+ srh = get_and_validate_srh(skb);
+ if (!srh)
+ goto drop;
+
+ advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
+
+ seg6_lookup_nexthop(skb, &slwt->nh6, 0);
+
+ return dst_input(skb);
+
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static int input_action_end_t(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ struct ipv6_sr_hdr *srh;
+
+ srh = get_and_validate_srh(skb);
+ if (!srh)
+ goto drop;
+
+ advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
+
+ seg6_lookup_nexthop(skb, NULL, slwt->table);
+
+ return dst_input(skb);
+
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+/* decapsulate and forward inner L2 frame on specified interface */
+static int input_action_end_dx2(struct sk_buff *skb,
+ struct seg6_local_lwt *slwt)
+{
+ struct net *net = dev_net(skb->dev);
+ struct net_device *odev;
+ struct ethhdr *eth;
+
+ if (!decap_and_validate(skb, NEXTHDR_NONE))
+ goto drop;
+
+ if (!pskb_may_pull(skb, ETH_HLEN))
+ goto drop;
+
+ skb_reset_mac_header(skb);
+ eth = (struct ethhdr *)skb->data;
+
+ /* To determine the frame's protocol, we assume it is 802.3. This avoids
+ * a call to eth_type_trans(), which is not really relevant for our
+ * use case.
+ */
+ if (!eth_proto_is_802_3(eth->h_proto))
+ goto drop;
+
+ odev = dev_get_by_index_rcu(net, slwt->oif);
+ if (!odev)
+ goto drop;
+
+ /* As we accept Ethernet frames, make sure the egress device is of
+ * the correct type.
+ */
+ if (odev->type != ARPHRD_ETHER)
+ goto drop;
+
+ if (!(odev->flags & IFF_UP) || !netif_carrier_ok(odev))
+ goto drop;
+
+ skb_orphan(skb);
+
+ if (skb_warn_if_lro(skb))
+ goto drop;
+
+ skb_forward_csum(skb);
+
+ if (skb->len - ETH_HLEN > odev->mtu)
+ goto drop;
+
+ skb->dev = odev;
+ skb->protocol = eth->h_proto;
+
+ return dev_queue_xmit(skb);
+
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+/* decapsulate and forward to specified nexthop */
+static int input_action_end_dx6(struct sk_buff *skb,
+ struct seg6_local_lwt *slwt)
+{
+ struct in6_addr *nhaddr = NULL;
+
+ /* this function accepts IPv6 encapsulated packets, with either
+ * an SRH with SL=0, or no SRH.
+ */
+
+ if (!decap_and_validate(skb, IPPROTO_IPV6))
+ goto drop;
+
+ if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
+ goto drop;
+
+ /* The inner packet is not associated to any local interface,
+ * so we do not call netif_rx().
+ *
+ * If slwt->nh6 is set to ::, then lookup the nexthop for the
+ * inner packet's DA. Otherwise, use the specified nexthop.
+ */
+
+ if (!ipv6_addr_any(&slwt->nh6))
+ nhaddr = &slwt->nh6;
+
+ seg6_lookup_nexthop(skb, nhaddr, 0);
+
+ return dst_input(skb);
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static int input_action_end_dx4(struct sk_buff *skb,
+ struct seg6_local_lwt *slwt)
+{
+ struct iphdr *iph;
+ __be32 nhaddr;
+ int err;
+
+ if (!decap_and_validate(skb, IPPROTO_IPIP))
+ goto drop;
+
+ if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+ goto drop;
+
+ skb->protocol = htons(ETH_P_IP);
+
+ iph = ip_hdr(skb);
+
+ nhaddr = slwt->nh4.s_addr ?: iph->daddr;
+
+ skb_dst_drop(skb);
+
+ err = ip_route_input(skb, nhaddr, iph->saddr, 0, skb->dev);
+ if (err)
+ goto drop;
+
+ return dst_input(skb);
+
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static int input_action_end_dt6(struct sk_buff *skb,
+ struct seg6_local_lwt *slwt)
+{
+ if (!decap_and_validate(skb, IPPROTO_IPV6))
+ goto drop;
+
+ if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
+ goto drop;
+
+ seg6_lookup_nexthop(skb, NULL, slwt->table);
+
+ return dst_input(skb);
+
+drop:
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+/* push an SRH on top of the current one */
+static int input_action_end_b6(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ struct ipv6_sr_hdr *srh;
+ int err = -EINVAL;
+
+ srh = get_and_validate_srh(skb);
+ if (!srh)
+ goto drop;
+
+ err = seg6_do_srh_inline(skb, slwt->srh);
+ if (err)
+ goto drop;
+
+ ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+ skb_set_transport_header(skb, sizeof(struct ipv6hdr));
+
+ seg6_lookup_nexthop(skb, NULL, 0);
+
+ return dst_input(skb);
+
+drop:
+ kfree_skb(skb);
+ return err;
+}
+
+/* encapsulate within an outer IPv6 header and a specified SRH */
+static int input_action_end_b6_encap(struct sk_buff *skb,
+ struct seg6_local_lwt *slwt)
+{
+ struct ipv6_sr_hdr *srh;
+ int err = -EINVAL;
+
+ srh = get_and_validate_srh(skb);
+ if (!srh)
+ goto drop;
+
+ advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
+
+ skb_reset_inner_headers(skb);
+ skb->encapsulation = 1;
+
+ err = seg6_do_srh_encap(skb, slwt->srh, IPPROTO_IPV6);
+ if (err)
+ goto drop;
+
+ ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+ skb_set_transport_header(skb, sizeof(struct ipv6hdr));
+
+ seg6_lookup_nexthop(skb, NULL, 0);
+
+ return dst_input(skb);
+
+drop:
+ kfree_skb(skb);
+ return err;
+}
+
+DEFINE_PER_CPU(struct seg6_bpf_srh_state, seg6_bpf_srh_states);
+
+bool seg6_bpf_has_valid_srh(struct sk_buff *skb)
+{
+ struct seg6_bpf_srh_state *srh_state =
+ this_cpu_ptr(&seg6_bpf_srh_states);
+ struct ipv6_sr_hdr *srh = srh_state->srh;
+
+ if (unlikely(srh == NULL))
+ return false;
+
+ if (unlikely(!srh_state->valid)) {
+ if ((srh_state->hdrlen & 7) != 0)
+ return false;
+
+ srh->hdrlen = (u8)(srh_state->hdrlen >> 3);
+ if (!seg6_validate_srh(srh, (srh->hdrlen + 1) << 3))
+ return false;
+
+ srh_state->valid = true;
+ }
+
+ return true;
+}
+
+static int input_action_end_bpf(struct sk_buff *skb,
+ struct seg6_local_lwt *slwt)
+{
+ struct seg6_bpf_srh_state *srh_state =
+ this_cpu_ptr(&seg6_bpf_srh_states);
+ struct ipv6_sr_hdr *srh;
+ int ret;
+
+ srh = get_and_validate_srh(skb);
+ if (!srh) {
+ kfree_skb(skb);
+ return -EINVAL;
+ }
+ advance_nextseg(srh, &ipv6_hdr(skb)->daddr);
+
+ /* preempt_disable is needed to protect the per-CPU buffer srh_state,
+ * which is also accessed by the bpf_lwt_seg6_* helpers
+ */
+ preempt_disable();
+ srh_state->srh = srh;
+ srh_state->hdrlen = srh->hdrlen << 3;
+ srh_state->valid = true;
+
+ rcu_read_lock();
+ bpf_compute_data_pointers(skb);
+ ret = bpf_prog_run_save_cb(slwt->bpf.prog, skb);
+ rcu_read_unlock();
+
+ switch (ret) {
+ case BPF_OK:
+ case BPF_REDIRECT:
+ break;
+ case BPF_DROP:
+ goto drop;
+ default:
+ pr_warn_once("bpf-seg6local: Illegal return value %u\n", ret);
+ goto drop;
+ }
+
+ if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
+ goto drop;
+
+ preempt_enable();
+ if (ret != BPF_REDIRECT)
+ seg6_lookup_nexthop(skb, NULL, 0);
+
+ return dst_input(skb);
+
+drop:
+ preempt_enable();
+ kfree_skb(skb);
+ return -EINVAL;
+}
+
+static struct seg6_action_desc seg6_action_table[] = {
+ {
+ .action = SEG6_LOCAL_ACTION_END,
+ .attrs = 0,
+ .input = input_action_end,
+ },
+ {
+ .action = SEG6_LOCAL_ACTION_END_X,
+ .attrs = (1 << SEG6_LOCAL_NH6),
+ .input = input_action_end_x,
+ },
+ {
+ .action = SEG6_LOCAL_ACTION_END_T,
+ .attrs = (1 << SEG6_LOCAL_TABLE),
+ .input = input_action_end_t,
+ },
+ {
+ .action = SEG6_LOCAL_ACTION_END_DX2,
+ .attrs = (1 << SEG6_LOCAL_OIF),
+ .input = input_action_end_dx2,
+ },
+ {
+ .action = SEG6_LOCAL_ACTION_END_DX6,
+ .attrs = (1 << SEG6_LOCAL_NH6),
+ .input = input_action_end_dx6,
+ },
+ {
+ .action = SEG6_LOCAL_ACTION_END_DX4,
+ .attrs = (1 << SEG6_LOCAL_NH4),
+ .input = input_action_end_dx4,
+ },
+ {
+ .action = SEG6_LOCAL_ACTION_END_DT6,
+ .attrs = (1 << SEG6_LOCAL_TABLE),
+ .input = input_action_end_dt6,
+ },
+ {
+ .action = SEG6_LOCAL_ACTION_END_B6,
+ .attrs = (1 << SEG6_LOCAL_SRH),
+ .input = input_action_end_b6,
+ },
+ {
+ .action = SEG6_LOCAL_ACTION_END_B6_ENCAP,
+ .attrs = (1 << SEG6_LOCAL_SRH),
+ .input = input_action_end_b6_encap,
+ .static_headroom = sizeof(struct ipv6hdr),
+ },
+ {
+ .action = SEG6_LOCAL_ACTION_END_BPF,
+ .attrs = (1 << SEG6_LOCAL_BPF),
+ .input = input_action_end_bpf,
+ },
+
+};
+
+static struct seg6_action_desc *__get_action_desc(int action)
+{
+ struct seg6_action_desc *desc;
+ int i, count;
+
+ count = ARRAY_SIZE(seg6_action_table);
+ for (i = 0; i < count; i++) {
+ desc = &seg6_action_table[i];
+ if (desc->action == action)
+ return desc;
+ }
+
+ return NULL;
+}
+
+static int seg6_local_input(struct sk_buff *skb)
+{
+ struct dst_entry *orig_dst = skb_dst(skb);
+ struct seg6_action_desc *desc;
+ struct seg6_local_lwt *slwt;
+
+ if (skb->protocol != htons(ETH_P_IPV6)) {
+ kfree_skb(skb);
+ return -EINVAL;
+ }
+
+ slwt = seg6_local_lwtunnel(orig_dst->lwtstate);
+ desc = slwt->desc;
+
+ return desc->input(skb, slwt);
+}
+
+static const struct nla_policy seg6_local_policy[SEG6_LOCAL_MAX + 1] = {
+ [SEG6_LOCAL_ACTION] = { .type = NLA_U32 },
+ [SEG6_LOCAL_SRH] = { .type = NLA_BINARY },
+ [SEG6_LOCAL_TABLE] = { .type = NLA_U32 },
+ [SEG6_LOCAL_NH4] = { .type = NLA_BINARY,
+ .len = sizeof(struct in_addr) },
+ [SEG6_LOCAL_NH6] = { .type = NLA_BINARY,
+ .len = sizeof(struct in6_addr) },
+ [SEG6_LOCAL_IIF] = { .type = NLA_U32 },
+ [SEG6_LOCAL_OIF] = { .type = NLA_U32 },
+ [SEG6_LOCAL_BPF] = { .type = NLA_NESTED },
+};
+
+static int parse_nla_srh(struct nlattr **attrs, struct seg6_local_lwt *slwt)
+{
+ struct ipv6_sr_hdr *srh;
+ int len;
+
+ srh = nla_data(attrs[SEG6_LOCAL_SRH]);
+ len = nla_len(attrs[SEG6_LOCAL_SRH]);
+
+ /* SRH must contain at least one segment */
+ if (len < sizeof(*srh) + sizeof(struct in6_addr))
+ return -EINVAL;
+
+ if (!seg6_validate_srh(srh, len))
+ return -EINVAL;
+
+ slwt->srh = kmemdup(srh, len, GFP_KERNEL);
+ if (!slwt->srh)
+ return -ENOMEM;
+
+ slwt->headroom += len;
+
+ return 0;
+}
+
+static int put_nla_srh(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ struct ipv6_sr_hdr *srh;
+ struct nlattr *nla;
+ int len;
+
+ srh = slwt->srh;
+ len = (srh->hdrlen + 1) << 3;
+
+ nla = nla_reserve(skb, SEG6_LOCAL_SRH, len);
+ if (!nla)
+ return -EMSGSIZE;
+
+ memcpy(nla_data(nla), srh, len);
+
+ return 0;
+}
+
+static int cmp_nla_srh(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
+{
+ int len = (a->srh->hdrlen + 1) << 3;
+
+ if (len != ((b->srh->hdrlen + 1) << 3))
+ return 1;
+
+ return memcmp(a->srh, b->srh, len);
+}
+
+static int parse_nla_table(struct nlattr **attrs, struct seg6_local_lwt *slwt)
+{
+ slwt->table = nla_get_u32(attrs[SEG6_LOCAL_TABLE]);
+
+ return 0;
+}
+
+static int put_nla_table(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ if (nla_put_u32(skb, SEG6_LOCAL_TABLE, slwt->table))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
+static int cmp_nla_table(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
+{
+ if (a->table != b->table)
+ return 1;
+
+ return 0;
+}
+
+static int parse_nla_nh4(struct nlattr **attrs, struct seg6_local_lwt *slwt)
+{
+ memcpy(&slwt->nh4, nla_data(attrs[SEG6_LOCAL_NH4]),
+ sizeof(struct in_addr));
+
+ return 0;
+}
+
+static int put_nla_nh4(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ struct nlattr *nla;
+
+ nla = nla_reserve(skb, SEG6_LOCAL_NH4, sizeof(struct in_addr));
+ if (!nla)
+ return -EMSGSIZE;
+
+ memcpy(nla_data(nla), &slwt->nh4, sizeof(struct in_addr));
+
+ return 0;
+}
+
+static int cmp_nla_nh4(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
+{
+ return memcmp(&a->nh4, &b->nh4, sizeof(struct in_addr));
+}
+
+static int parse_nla_nh6(struct nlattr **attrs, struct seg6_local_lwt *slwt)
+{
+ memcpy(&slwt->nh6, nla_data(attrs[SEG6_LOCAL_NH6]),
+ sizeof(struct in6_addr));
+
+ return 0;
+}
+
+static int put_nla_nh6(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ struct nlattr *nla;
+
+ nla = nla_reserve(skb, SEG6_LOCAL_NH6, sizeof(struct in6_addr));
+ if (!nla)
+ return -EMSGSIZE;
+
+ memcpy(nla_data(nla), &slwt->nh6, sizeof(struct in6_addr));
+
+ return 0;
+}
+
+static int cmp_nla_nh6(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
+{
+ return memcmp(&a->nh6, &b->nh6, sizeof(struct in6_addr));
+}
+
+static int parse_nla_iif(struct nlattr **attrs, struct seg6_local_lwt *slwt)
+{
+ slwt->iif = nla_get_u32(attrs[SEG6_LOCAL_IIF]);
+
+ return 0;
+}
+
+static int put_nla_iif(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ if (nla_put_u32(skb, SEG6_LOCAL_IIF, slwt->iif))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
+static int cmp_nla_iif(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
+{
+ if (a->iif != b->iif)
+ return 1;
+
+ return 0;
+}
+
+static int parse_nla_oif(struct nlattr **attrs, struct seg6_local_lwt *slwt)
+{
+ slwt->oif = nla_get_u32(attrs[SEG6_LOCAL_OIF]);
+
+ return 0;
+}
+
+static int put_nla_oif(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ if (nla_put_u32(skb, SEG6_LOCAL_OIF, slwt->oif))
+ return -EMSGSIZE;
+
+ return 0;
+}
+
+static int cmp_nla_oif(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
+{
+ if (a->oif != b->oif)
+ return 1;
+
+ return 0;
+}
+
+#define MAX_PROG_NAME 256
+static const struct nla_policy bpf_prog_policy[SEG6_LOCAL_BPF_PROG_MAX + 1] = {
+ [SEG6_LOCAL_BPF_PROG] = { .type = NLA_U32, },
+ [SEG6_LOCAL_BPF_PROG_NAME] = { .type = NLA_NUL_STRING,
+ .len = MAX_PROG_NAME },
+};
+
+static int parse_nla_bpf(struct nlattr **attrs, struct seg6_local_lwt *slwt)
+{
+ struct nlattr *tb[SEG6_LOCAL_BPF_PROG_MAX + 1];
+ struct bpf_prog *p;
+ int ret;
+ u32 fd;
+
+ ret = nla_parse_nested(tb, SEG6_LOCAL_BPF_PROG_MAX,
+ attrs[SEG6_LOCAL_BPF], bpf_prog_policy, NULL);
+ if (ret < 0)
+ return ret;
+
+ if (!tb[SEG6_LOCAL_BPF_PROG] || !tb[SEG6_LOCAL_BPF_PROG_NAME])
+ return -EINVAL;
+
+ slwt->bpf.name = nla_memdup(tb[SEG6_LOCAL_BPF_PROG_NAME], GFP_KERNEL);
+ if (!slwt->bpf.name)
+ return -ENOMEM;
+
+ fd = nla_get_u32(tb[SEG6_LOCAL_BPF_PROG]);
+ p = bpf_prog_get_type(fd, BPF_PROG_TYPE_LWT_SEG6LOCAL);
+ if (IS_ERR(p)) {
+ kfree(slwt->bpf.name);
+ return PTR_ERR(p);
+ }
+
+ slwt->bpf.prog = p;
+ return 0;
+}
+
+static int put_nla_bpf(struct sk_buff *skb, struct seg6_local_lwt *slwt)
+{
+ struct nlattr *nest;
+
+ if (!slwt->bpf.prog)
+ return 0;
+
+ nest = nla_nest_start(skb, SEG6_LOCAL_BPF);
+ if (!nest)
+ return -EMSGSIZE;
+
+ if (nla_put_u32(skb, SEG6_LOCAL_BPF_PROG, slwt->bpf.prog->aux->id))
+ return -EMSGSIZE;
+
+ if (slwt->bpf.name &&
+ nla_put_string(skb, SEG6_LOCAL_BPF_PROG_NAME, slwt->bpf.name))
+ return -EMSGSIZE;
+
+ return nla_nest_end(skb, nest);
+}
+
+static int cmp_nla_bpf(struct seg6_local_lwt *a, struct seg6_local_lwt *b)
+{
+ if (!a->bpf.name && !b->bpf.name)
+ return 0;
+
+ if (!a->bpf.name || !b->bpf.name)
+ return 1;
+
+ return strcmp(a->bpf.name, b->bpf.name);
+}
+
+struct seg6_action_param {
+ int (*parse)(struct nlattr **attrs, struct seg6_local_lwt *slwt);
+ int (*put)(struct sk_buff *skb, struct seg6_local_lwt *slwt);
+ int (*cmp)(struct seg6_local_lwt *a, struct seg6_local_lwt *b);
+};
+
+static struct seg6_action_param seg6_action_params[SEG6_LOCAL_MAX + 1] = {
+ [SEG6_LOCAL_SRH] = { .parse = parse_nla_srh,
+ .put = put_nla_srh,
+ .cmp = cmp_nla_srh },
+
+ [SEG6_LOCAL_TABLE] = { .parse = parse_nla_table,
+ .put = put_nla_table,
+ .cmp = cmp_nla_table },
+
+ [SEG6_LOCAL_NH4] = { .parse = parse_nla_nh4,
+ .put = put_nla_nh4,
+ .cmp = cmp_nla_nh4 },
+
+ [SEG6_LOCAL_NH6] = { .parse = parse_nla_nh6,
+ .put = put_nla_nh6,
+ .cmp = cmp_nla_nh6 },
+
+ [SEG6_LOCAL_IIF] = { .parse = parse_nla_iif,
+ .put = put_nla_iif,
+ .cmp = cmp_nla_iif },
+
+ [SEG6_LOCAL_OIF] = { .parse = parse_nla_oif,
+ .put = put_nla_oif,
+ .cmp = cmp_nla_oif },
+
+ [SEG6_LOCAL_BPF] = { .parse = parse_nla_bpf,
+ .put = put_nla_bpf,
+ .cmp = cmp_nla_bpf },
+
+};
+
+static int parse_nla_action(struct nlattr **attrs, struct seg6_local_lwt *slwt)
+{
+ struct seg6_action_param *param;
+ struct seg6_action_desc *desc;
+ int i, err;
+
+ desc = __get_action_desc(slwt->action);
+ if (!desc)
+ return -EINVAL;
+
+ if (!desc->input)
+ return -EOPNOTSUPP;
+
+ slwt->desc = desc;
+ slwt->headroom += desc->static_headroom;
+
+ for (i = 0; i < SEG6_LOCAL_MAX + 1; i++) {
+ if (desc->attrs & (1 << i)) {
+ if (!attrs[i])
+ return -EINVAL;
+
+ param = &seg6_action_params[i];
+
+ err = param->parse(attrs, slwt);
+ if (err < 0)
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int seg6_local_build_state(struct nlattr *nla, unsigned int family,
+ const void *cfg, struct lwtunnel_state **ts,
+ struct netlink_ext_ack *extack)
+{
+ struct nlattr *tb[SEG6_LOCAL_MAX + 1];
+ struct lwtunnel_state *newts;
+ struct seg6_local_lwt *slwt;
+ int err;
+
+ if (family != AF_INET6)
+ return -EINVAL;
+
+ err = nla_parse_nested(tb, SEG6_LOCAL_MAX, nla, seg6_local_policy,
+ extack);
+
+ if (err < 0)
+ return err;
+
+ if (!tb[SEG6_LOCAL_ACTION])
+ return -EINVAL;
+
+ newts = lwtunnel_state_alloc(sizeof(*slwt));
+ if (!newts)
+ return -ENOMEM;
+
+ slwt = seg6_local_lwtunnel(newts);
+ slwt->action = nla_get_u32(tb[SEG6_LOCAL_ACTION]);
+
+ err = parse_nla_action(tb, slwt);
+ if (err < 0)
+ goto out_free;
+
+ newts->type = LWTUNNEL_ENCAP_SEG6_LOCAL;
+ newts->flags = LWTUNNEL_STATE_INPUT_REDIRECT;
+ newts->headroom = slwt->headroom;
+
+ *ts = newts;
+
+ return 0;
+
+out_free:
+ kfree(slwt->srh);
+ kfree(newts);
+ return err;
+}
+
+static void seg6_local_destroy_state(struct lwtunnel_state *lwt)
+{
+ struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
+
+ kfree(slwt->srh);
+
+ if (slwt->desc->attrs & (1 << SEG6_LOCAL_BPF)) {
+ kfree(slwt->bpf.name);
+ bpf_prog_put(slwt->bpf.prog);
+ }
+
+ return;
+}
+
+static int seg6_local_fill_encap(struct sk_buff *skb,
+ struct lwtunnel_state *lwt)
+{
+ struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
+ struct seg6_action_param *param;
+ int i, err;
+
+ if (nla_put_u32(skb, SEG6_LOCAL_ACTION, slwt->action))
+ return -EMSGSIZE;
+
+ for (i = 0; i < SEG6_LOCAL_MAX + 1; i++) {
+ if (slwt->desc->attrs & (1 << i)) {
+ param = &seg6_action_params[i];
+ err = param->put(skb, slwt);
+ if (err < 0)
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int seg6_local_get_encap_size(struct lwtunnel_state *lwt)
+{
+ struct seg6_local_lwt *slwt = seg6_local_lwtunnel(lwt);
+ unsigned long attrs;
+ int nlsize;
+
+ nlsize = nla_total_size(4); /* action */
+
+ attrs = slwt->desc->attrs;
+
+ if (attrs & (1 << SEG6_LOCAL_SRH))
+ nlsize += nla_total_size((slwt->srh->hdrlen + 1) << 3);
+
+ if (attrs & (1 << SEG6_LOCAL_TABLE))
+ nlsize += nla_total_size(4);
+
+ if (attrs & (1 << SEG6_LOCAL_NH4))
+ nlsize += nla_total_size(4);
+
+ if (attrs & (1 << SEG6_LOCAL_NH6))
+ nlsize += nla_total_size(16);
+
+ if (attrs & (1 << SEG6_LOCAL_IIF))
+ nlsize += nla_total_size(4);
+
+ if (attrs & (1 << SEG6_LOCAL_OIF))
+ nlsize += nla_total_size(4);
+
+ if (attrs & (1 << SEG6_LOCAL_BPF))
+ nlsize += nla_total_size(sizeof(struct nlattr)) +
+ nla_total_size(MAX_PROG_NAME) +
+ nla_total_size(4);
+
+ return nlsize;
+}
+
+static int seg6_local_cmp_encap(struct lwtunnel_state *a,
+ struct lwtunnel_state *b)
+{
+ struct seg6_local_lwt *slwt_a, *slwt_b;
+ struct seg6_action_param *param;
+ int i;
+
+ slwt_a = seg6_local_lwtunnel(a);
+ slwt_b = seg6_local_lwtunnel(b);
+
+ if (slwt_a->action != slwt_b->action)
+ return 1;
+
+ if (slwt_a->desc->attrs != slwt_b->desc->attrs)
+ return 1;
+
+ for (i = 0; i < SEG6_LOCAL_MAX + 1; i++) {
+ if (slwt_a->desc->attrs & (1 << i)) {
+ param = &seg6_action_params[i];
+ if (param->cmp(slwt_a, slwt_b))
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+static const struct lwtunnel_encap_ops seg6_local_ops = {
+ .build_state = seg6_local_build_state,
+ .destroy_state = seg6_local_destroy_state,
+ .input = seg6_local_input,
+ .fill_encap = seg6_local_fill_encap,
+ .get_encap_size = seg6_local_get_encap_size,
+ .cmp_encap = seg6_local_cmp_encap,
+ .owner = THIS_MODULE,
+};
+
+int __init seg6_local_init(void)
+{
+ return lwtunnel_encap_add_ops(&seg6_local_ops,
+ LWTUNNEL_ENCAP_SEG6_LOCAL);
+}
+
+void seg6_local_exit(void)
+{
+ lwtunnel_encap_del_ops(&seg6_local_ops, LWTUNNEL_ENCAP_SEG6_LOCAL);
+}