// SPDX-License-Identifier: GPL-2.0-or-later /* Copyright (c) 2021 Taehee Yoo */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static struct workqueue_struct *amt_wq; static HLIST_HEAD(source_gc_list); /* Lock for source_gc_list */ static spinlock_t source_gc_lock; static struct delayed_work source_gc_wq; static char *status_str[] = { "AMT_STATUS_INIT", "AMT_STATUS_SENT_DISCOVERY", "AMT_STATUS_RECEIVED_DISCOVERY", "AMT_STATUS_SENT_ADVERTISEMENT", "AMT_STATUS_RECEIVED_ADVERTISEMENT", "AMT_STATUS_SENT_REQUEST", "AMT_STATUS_RECEIVED_REQUEST", "AMT_STATUS_SENT_QUERY", "AMT_STATUS_RECEIVED_QUERY", "AMT_STATUS_SENT_UPDATE", "AMT_STATUS_RECEIVED_UPDATE", }; static char *type_str[] = { "", /* Type 0 is not defined */ "AMT_MSG_DISCOVERY", "AMT_MSG_ADVERTISEMENT", "AMT_MSG_REQUEST", "AMT_MSG_MEMBERSHIP_QUERY", "AMT_MSG_MEMBERSHIP_UPDATE", "AMT_MSG_MULTICAST_DATA", "AMT_MSG_TEARDOWN", }; static char *action_str[] = { "AMT_ACT_GMI", "AMT_ACT_GMI_ZERO", "AMT_ACT_GT", "AMT_ACT_STATUS_FWD_NEW", "AMT_ACT_STATUS_D_FWD_NEW", "AMT_ACT_STATUS_NONE_NEW", }; static struct igmpv3_grec igmpv3_zero_grec; #if IS_ENABLED(CONFIG_IPV6) #define MLD2_ALL_NODE_INIT { { { 0xff, 0x02, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01 } } } static struct in6_addr mld2_all_node = MLD2_ALL_NODE_INIT; static struct mld2_grec mldv2_zero_grec; #endif static struct amt_skb_cb *amt_skb_cb(struct sk_buff *skb) { BUILD_BUG_ON(sizeof(struct amt_skb_cb) + sizeof(struct tc_skb_cb) > sizeof_field(struct sk_buff, cb)); return (struct amt_skb_cb *)((void *)skb->cb + sizeof(struct tc_skb_cb)); } static void __amt_source_gc_work(void) { struct amt_source_node *snode; struct hlist_head gc_list; struct hlist_node *t; spin_lock_bh(&source_gc_lock); hlist_move_list(&source_gc_list, &gc_list); spin_unlock_bh(&source_gc_lock); hlist_for_each_entry_safe(snode, t, &gc_list, node) { hlist_del_rcu(&snode->node); kfree_rcu(snode, rcu); } } static void amt_source_gc_work(struct work_struct *work) { __amt_source_gc_work(); spin_lock_bh(&source_gc_lock); mod_delayed_work(amt_wq, &source_gc_wq, msecs_to_jiffies(AMT_GC_INTERVAL)); spin_unlock_bh(&source_gc_lock); } static bool amt_addr_equal(union amt_addr *a, union amt_addr *b) { return !memcmp(a, b, sizeof(union amt_addr)); } static u32 amt_source_hash(struct amt_tunnel_list *tunnel, union amt_addr *src) { u32 hash = jhash(src, sizeof(*src), tunnel->amt->hash_seed); return reciprocal_scale(hash, tunnel->amt->hash_buckets); } static bool amt_status_filter(struct amt_source_node *snode, enum amt_filter filter) { bool rc = false; switch (filter) { case AMT_FILTER_FWD: if (snode->status == AMT_SOURCE_STATUS_FWD && snode->flags == AMT_SOURCE_OLD) rc = true; break; case AMT_FILTER_D_FWD: if (snode->status == AMT_SOURCE_STATUS_D_FWD && snode->flags == AMT_SOURCE_OLD) rc = true; break; case AMT_FILTER_FWD_NEW: if (snode->status == AMT_SOURCE_STATUS_FWD && snode->flags == AMT_SOURCE_NEW) rc = true; break; case AMT_FILTER_D_FWD_NEW: if (snode->status == AMT_SOURCE_STATUS_D_FWD && snode->flags == AMT_SOURCE_NEW) rc = true; break; case AMT_FILTER_ALL: rc = true; break; case AMT_FILTER_NONE_NEW: if (snode->status == AMT_SOURCE_STATUS_NONE && snode->flags == AMT_SOURCE_NEW) rc = true; break; case AMT_FILTER_BOTH: if ((snode->status == AMT_SOURCE_STATUS_D_FWD || snode->status == AMT_SOURCE_STATUS_FWD) && snode->flags == AMT_SOURCE_OLD) rc = true; break; case AMT_FILTER_BOTH_NEW: if ((snode->status == AMT_SOURCE_STATUS_D_FWD || snode->status == AMT_SOURCE_STATUS_FWD) && snode->flags == AMT_SOURCE_NEW) rc = true; break; default: WARN_ON_ONCE(1); break; } return rc; } static struct amt_source_node *amt_lookup_src(struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, enum amt_filter filter, union amt_addr *src) { u32 hash = amt_source_hash(tunnel, src); struct amt_source_node *snode; hlist_for_each_entry_rcu(snode, &gnode->sources[hash], node) if (amt_status_filter(snode, filter) && amt_addr_equal(&snode->source_addr, src)) return snode; return NULL; } static u32 amt_group_hash(struct amt_tunnel_list *tunnel, union amt_addr *group) { u32 hash = jhash(group, sizeof(*group), tunnel->amt->hash_seed); return reciprocal_scale(hash, tunnel->amt->hash_buckets); } static struct amt_group_node *amt_lookup_group(struct amt_tunnel_list *tunnel, union amt_addr *group, union amt_addr *host, bool v6) { u32 hash = amt_group_hash(tunnel, group); struct amt_group_node *gnode; hlist_for_each_entry_rcu(gnode, &tunnel->groups[hash], node) { if (amt_addr_equal(&gnode->group_addr, group) && amt_addr_equal(&gnode->host_addr, host) && gnode->v6 == v6) return gnode; } return NULL; } static void amt_destroy_source(struct amt_source_node *snode) { struct amt_group_node *gnode = snode->gnode; struct amt_tunnel_list *tunnel; tunnel = gnode->tunnel_list; if (!gnode->v6) { netdev_dbg(snode->gnode->amt->dev, "Delete source %pI4 from %pI4\n", &snode->source_addr.ip4, &gnode->group_addr.ip4); #if IS_ENABLED(CONFIG_IPV6) } else { netdev_dbg(snode->gnode->amt->dev, "Delete source %pI6 from %pI6\n", &snode->source_addr.ip6, &gnode->group_addr.ip6); #endif } cancel_delayed_work(&snode->source_timer); hlist_del_init_rcu(&snode->node); tunnel->nr_sources--; gnode->nr_sources--; spin_lock_bh(&source_gc_lock); hlist_add_head_rcu(&snode->node, &source_gc_list); spin_unlock_bh(&source_gc_lock); } static void amt_del_group(struct amt_dev *amt, struct amt_group_node *gnode) { struct amt_source_node *snode; struct hlist_node *t; int i; if (cancel_delayed_work(&gnode->group_timer)) dev_put(amt->dev); hlist_del_rcu(&gnode->node); gnode->tunnel_list->nr_groups--; if (!gnode->v6) netdev_dbg(amt->dev, "Leave group %pI4\n", &gnode->group_addr.ip4); #if IS_ENABLED(CONFIG_IPV6) else netdev_dbg(amt->dev, "Leave group %pI6\n", &gnode->group_addr.ip6); #endif for (i = 0; i < amt->hash_buckets; i++) hlist_for_each_entry_safe(snode, t, &gnode->sources[i], node) amt_destroy_source(snode); /* tunnel->lock was acquired outside of amt_del_group() * But rcu_read_lock() was acquired too so It's safe. */ kfree_rcu(gnode, rcu); } /* If a source timer expires with a router filter-mode for the group of * INCLUDE, the router concludes that traffic from this particular * source is no longer desired on the attached network, and deletes the * associated source record. */ static void amt_source_work(struct work_struct *work) { struct amt_source_node *snode = container_of(to_delayed_work(work), struct amt_source_node, source_timer); struct amt_group_node *gnode = snode->gnode; struct amt_dev *amt = gnode->amt; struct amt_tunnel_list *tunnel; tunnel = gnode->tunnel_list; spin_lock_bh(&tunnel->lock); rcu_read_lock(); if (gnode->filter_mode == MCAST_INCLUDE) { amt_destroy_source(snode); if (!gnode->nr_sources) amt_del_group(amt, gnode); } else { /* When a router filter-mode for a group is EXCLUDE, * source records are only deleted when the group timer expires */ snode->status = AMT_SOURCE_STATUS_D_FWD; } rcu_read_unlock(); spin_unlock_bh(&tunnel->lock); } static void amt_act_src(struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, struct amt_source_node *snode, enum amt_act act) { struct amt_dev *amt = tunnel->amt; switch (act) { case AMT_ACT_GMI: mod_delayed_work(amt_wq, &snode->source_timer, msecs_to_jiffies(amt_gmi(amt))); break; case AMT_ACT_GMI_ZERO: cancel_delayed_work(&snode->source_timer); break; case AMT_ACT_GT: mod_delayed_work(amt_wq, &snode->source_timer, gnode->group_timer.timer.expires); break; case AMT_ACT_STATUS_FWD_NEW: snode->status = AMT_SOURCE_STATUS_FWD; snode->flags = AMT_SOURCE_NEW; break; case AMT_ACT_STATUS_D_FWD_NEW: snode->status = AMT_SOURCE_STATUS_D_FWD; snode->flags = AMT_SOURCE_NEW; break; case AMT_ACT_STATUS_NONE_NEW: cancel_delayed_work(&snode->source_timer); snode->status = AMT_SOURCE_STATUS_NONE; snode->flags = AMT_SOURCE_NEW; break; default: WARN_ON_ONCE(1); return; } if (!gnode->v6) netdev_dbg(amt->dev, "Source %pI4 from %pI4 Acted %s\n", &snode->source_addr.ip4, &gnode->group_addr.ip4, action_str[act]); #if IS_ENABLED(CONFIG_IPV6) else netdev_dbg(amt->dev, "Source %pI6 from %pI6 Acted %s\n", &snode->source_addr.ip6, &gnode->group_addr.ip6, action_str[act]); #endif } static struct amt_source_node *amt_alloc_snode(struct amt_group_node *gnode, union amt_addr *src) { struct amt_source_node *snode; snode = kzalloc(sizeof(*snode), GFP_ATOMIC); if (!snode) return NULL; memcpy(&snode->source_addr, src, sizeof(union amt_addr)); snode->gnode = gnode; snode->status = AMT_SOURCE_STATUS_NONE; snode->flags = AMT_SOURCE_NEW; INIT_HLIST_NODE(&snode->node); INIT_DELAYED_WORK(&snode->source_timer, amt_source_work); return snode; } /* RFC 3810 - 7.2.2. Definition of Filter Timers * * Router Mode Filter Timer Actions/Comments * ----------- ----------------- ---------------- * * INCLUDE Not Used All listeners in * INCLUDE mode. * * EXCLUDE Timer > 0 At least one listener * in EXCLUDE mode. * * EXCLUDE Timer == 0 No more listeners in * EXCLUDE mode for the * multicast address. * If the Requested List * is empty, delete * Multicast Address * Record. If not, switch * to INCLUDE filter mode; * the sources in the * Requested List are * moved to the Include * List, and the Exclude * List is deleted. */ static void amt_group_work(struct work_struct *work) { struct amt_group_node *gnode = container_of(to_delayed_work(work), struct amt_group_node, group_timer); struct amt_tunnel_list *tunnel = gnode->tunnel_list; struct amt_dev *amt = gnode->amt; struct amt_source_node *snode; bool delete_group = true; struct hlist_node *t; int i, buckets; buckets = amt->hash_buckets; spin_lock_bh(&tunnel->lock); if (gnode->filter_mode == MCAST_INCLUDE) { /* Not Used */ spin_unlock_bh(&tunnel->lock); goto out; } rcu_read_lock(); for (i = 0; i < buckets; i++) { hlist_for_each_entry_safe(snode, t, &gnode->sources[i], node) { if (!delayed_work_pending(&snode->source_timer) || snode->status == AMT_SOURCE_STATUS_D_FWD) { amt_destroy_source(snode); } else { delete_group = false; snode->status = AMT_SOURCE_STATUS_FWD; } } } if (delete_group) amt_del_group(amt, gnode); else gnode->filter_mode = MCAST_INCLUDE; rcu_read_unlock(); spin_unlock_bh(&tunnel->lock); out: dev_put(amt->dev); } /* Non-existent group is created as INCLUDE {empty}: * * RFC 3376 - 5.1. Action on Change of Interface State * * If no interface state existed for that multicast address before * the change (i.e., the change consisted of creating a new * per-interface record), or if no state exists after the change * (i.e., the change consisted of deleting a per-interface record), * then the "non-existent" state is considered to have a filter mode * of INCLUDE and an empty source list. */ static struct amt_group_node *amt_add_group(struct amt_dev *amt, struct amt_tunnel_list *tunnel, union amt_addr *group, union amt_addr *host, bool v6) { struct amt_group_node *gnode; u32 hash; int i; if (tunnel->nr_groups >= amt->max_groups) return ERR_PTR(-ENOSPC); gnode = kzalloc(sizeof(*gnode) + (sizeof(struct hlist_head) * amt->hash_buckets), GFP_ATOMIC); if (unlikely(!gnode)) return ERR_PTR(-ENOMEM); gnode->amt = amt; gnode->group_addr = *group; gnode->host_addr = *host; gnode->v6 = v6; gnode->tunnel_list = tunnel; gnode->filter_mode = MCAST_INCLUDE; INIT_HLIST_NODE(&gnode->node); INIT_DELAYED_WORK(&gnode->group_timer, amt_group_work); for (i = 0; i < amt->hash_buckets; i++) INIT_HLIST_HEAD(&gnode->sources[i]); hash = amt_group_hash(tunnel, group); hlist_add_head_rcu(&gnode->node, &tunnel->groups[hash]); tunnel->nr_groups++; if (!gnode->v6) netdev_dbg(amt->dev, "Join group %pI4\n", &gnode->group_addr.ip4); #if IS_ENABLED(CONFIG_IPV6) else netdev_dbg(amt->dev, "Join group %pI6\n", &gnode->group_addr.ip6); #endif return gnode; } static struct sk_buff *amt_build_igmp_gq(struct amt_dev *amt) { u8 ra[AMT_IPHDR_OPTS] = { IPOPT_RA, 4, 0, 0 }; int hlen = LL_RESERVED_SPACE(amt->dev); int tlen = amt->dev->needed_tailroom; struct igmpv3_query *ihv3; void *csum_start = NULL; __sum16 *csum = NULL; struct sk_buff *skb; struct ethhdr *eth; struct iphdr *iph; unsigned int len; int offset; len = hlen + tlen + sizeof(*iph) + AMT_IPHDR_OPTS + sizeof(*ihv3); skb = netdev_alloc_skb_ip_align(amt->dev, len); if (!skb) return NULL; skb_reserve(skb, hlen); skb_push(skb, sizeof(*eth)); skb->protocol = htons(ETH_P_IP); skb_reset_mac_header(skb); skb->priority = TC_PRIO_CONTROL; skb_put(skb, sizeof(*iph)); skb_put_data(skb, ra, sizeof(ra)); skb_put(skb, sizeof(*ihv3)); skb_pull(skb, sizeof(*eth)); skb_reset_network_header(skb); iph = ip_hdr(skb); iph->version = 4; iph->ihl = (sizeof(struct iphdr) + AMT_IPHDR_OPTS) >> 2; iph->tos = AMT_TOS; iph->tot_len = htons(sizeof(*iph) + AMT_IPHDR_OPTS + sizeof(*ihv3)); iph->frag_off = htons(IP_DF); iph->ttl = 1; iph->id = 0; iph->protocol = IPPROTO_IGMP; iph->daddr = htonl(INADDR_ALLHOSTS_GROUP); iph->saddr = htonl(INADDR_ANY); ip_send_check(iph); eth = eth_hdr(skb); ether_addr_copy(eth->h_source, amt->dev->dev_addr); ip_eth_mc_map(htonl(INADDR_ALLHOSTS_GROUP), eth->h_dest); eth->h_proto = htons(ETH_P_IP); ihv3 = skb_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS); skb_reset_transport_header(skb); ihv3->type = IGMP_HOST_MEMBERSHIP_QUERY; ihv3->code = 1; ihv3->group = 0; ihv3->qqic = amt->qi; ihv3->nsrcs = 0; ihv3->resv = 0; ihv3->suppress = false; ihv3->qrv = READ_ONCE(amt->net->ipv4.sysctl_igmp_qrv); ihv3->csum = 0; csum = &ihv3->csum; csum_start = (void *)ihv3; *csum = ip_compute_csum(csum_start, sizeof(*ihv3)); offset = skb_transport_offset(skb); skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); skb->ip_summed = CHECKSUM_NONE; skb_push(skb, sizeof(*eth) + sizeof(*iph) + AMT_IPHDR_OPTS); return skb; } static void amt_update_gw_status(struct amt_dev *amt, enum amt_status status, bool validate) { if (validate && amt->status >= status) return; netdev_dbg(amt->dev, "Update GW status %s -> %s", status_str[amt->status], status_str[status]); WRITE_ONCE(amt->status, status); } static void __amt_update_relay_status(struct amt_tunnel_list *tunnel, enum amt_status status, bool validate) { if (validate && tunnel->status >= status) return; netdev_dbg(tunnel->amt->dev, "Update Tunnel(IP = %pI4, PORT = %u) status %s -> %s", &tunnel->ip4, ntohs(tunnel->source_port), status_str[tunnel->status], status_str[status]); tunnel->status = status; } static void amt_update_relay_status(struct amt_tunnel_list *tunnel, enum amt_status status, bool validate) { spin_lock_bh(&tunnel->lock); __amt_update_relay_status(tunnel, status, validate); spin_unlock_bh(&tunnel->lock); } static void amt_send_discovery(struct amt_dev *amt) { struct amt_header_discovery *amtd; int hlen, tlen, offset; struct socket *sock; struct udphdr *udph; struct sk_buff *skb; struct iphdr *iph; struct rtable *rt; struct flowi4 fl4; u32 len; int err; rcu_read_lock(); sock = rcu_dereference(amt->sock); if (!sock) goto out; if (!netif_running(amt->stream_dev) || !netif_running(amt->dev)) goto out; rt = ip_route_output_ports(amt->net, &fl4, sock->sk, amt->discovery_ip, amt->local_ip, amt->gw_port, amt->relay_port, IPPROTO_UDP, 0, amt->stream_dev->ifindex); if (IS_ERR(rt)) { amt->dev->stats.tx_errors++; goto out; } hlen = LL_RESERVED_SPACE(amt->dev); tlen = amt->dev->needed_tailroom; len = hlen + tlen + sizeof(*iph) + sizeof(*udph) + sizeof(*amtd); skb = netdev_alloc_skb_ip_align(amt->dev, len); if (!skb) { ip_rt_put(rt); amt->dev->stats.tx_errors++; goto out; } skb->priority = TC_PRIO_CONTROL; skb_dst_set(skb, &rt->dst); len = sizeof(*iph) + sizeof(*udph) + sizeof(*amtd); skb_reset_network_header(skb); skb_put(skb, len); amtd = skb_pull(skb, sizeof(*iph) + sizeof(*udph)); amtd->version = 0; amtd->type = AMT_MSG_DISCOVERY; amtd->reserved = 0; amtd->nonce = amt->nonce; skb_push(skb, sizeof(*udph)); skb_reset_transport_header(skb); udph = udp_hdr(skb); udph->source = amt->gw_port; udph->dest = amt->relay_port; udph->len = htons(sizeof(*udph) + sizeof(*amtd)); udph->check = 0; offset = skb_transport_offset(skb); skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); udph->check = csum_tcpudp_magic(amt->local_ip, amt->discovery_ip, sizeof(*udph) + sizeof(*amtd), IPPROTO_UDP, skb->csum); skb_push(skb, sizeof(*iph)); iph = ip_hdr(skb); iph->version = 4; iph->ihl = (sizeof(struct iphdr)) >> 2; iph->tos = AMT_TOS; iph->frag_off = 0; iph->ttl = ip4_dst_hoplimit(&rt->dst); iph->daddr = amt->discovery_ip; iph->saddr = amt->local_ip; iph->protocol = IPPROTO_UDP; iph->tot_len = htons(len); skb->ip_summed = CHECKSUM_NONE; ip_select_ident(amt->net, skb, NULL); ip_send_check(iph); err = ip_local_out(amt->net, sock->sk, skb); if (unlikely(net_xmit_eval(err))) amt->dev->stats.tx_errors++; amt_update_gw_status(amt, AMT_STATUS_SENT_DISCOVERY, true); out: rcu_read_unlock(); } static void amt_send_request(struct amt_dev *amt, bool v6) { struct amt_header_request *amtrh; int hlen, tlen, offset; struct socket *sock; struct udphdr *udph; struct sk_buff *skb; struct iphdr *iph; struct rtable *rt; struct flowi4 fl4; u32 len; int err; rcu_read_lock(); sock = rcu_dereference(amt->sock); if (!sock) goto out; if (!netif_running(amt->stream_dev) || !netif_running(amt->dev)) goto out; rt = ip_route_output_ports(amt->net, &fl4, sock->sk, amt->remote_ip, amt->local_ip, amt->gw_port, amt->relay_port, IPPROTO_UDP, 0, amt->stream_dev->ifindex); if (IS_ERR(rt)) { amt->dev->stats.tx_errors++; goto out; } hlen = LL_RESERVED_SPACE(amt->dev); tlen = amt->dev->needed_tailroom; len = hlen + tlen + sizeof(*iph) + sizeof(*udph) + sizeof(*amtrh); skb = netdev_alloc_skb_ip_align(amt->dev, len); if (!skb) { ip_rt_put(rt); amt->dev->stats.tx_errors++; goto out; } skb->priority = TC_PRIO_CONTROL; skb_dst_set(skb, &rt->dst); len = sizeof(*iph) + sizeof(*udph) + sizeof(*amtrh); skb_reset_network_header(skb); skb_put(skb, len); amtrh = skb_pull(skb, sizeof(*iph) + sizeof(*udph)); amtrh->version = 0; amtrh->type = AMT_MSG_REQUEST; amtrh->reserved1 = 0; amtrh->p = v6; amtrh->reserved2 = 0; amtrh->nonce = amt->nonce; skb_push(skb, sizeof(*udph)); skb_reset_transport_header(skb); udph = udp_hdr(skb); udph->source = amt->gw_port; udph->dest = amt->relay_port; udph->len = htons(sizeof(*amtrh) + sizeof(*udph)); udph->check = 0; offset = skb_transport_offset(skb); skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); udph->check = csum_tcpudp_magic(amt->local_ip, amt->remote_ip, sizeof(*udph) + sizeof(*amtrh), IPPROTO_UDP, skb->csum); skb_push(skb, sizeof(*iph)); iph = ip_hdr(skb); iph->version = 4; iph->ihl = (sizeof(struct iphdr)) >> 2; iph->tos = AMT_TOS; iph->frag_off = 0; iph->ttl = ip4_dst_hoplimit(&rt->dst); iph->daddr = amt->remote_ip; iph->saddr = amt->local_ip; iph->protocol = IPPROTO_UDP; iph->tot_len = htons(len); skb->ip_summed = CHECKSUM_NONE; ip_select_ident(amt->net, skb, NULL); ip_send_check(iph); err = ip_local_out(amt->net, sock->sk, skb); if (unlikely(net_xmit_eval(err))) amt->dev->stats.tx_errors++; out: rcu_read_unlock(); } static void amt_send_igmp_gq(struct amt_dev *amt, struct amt_tunnel_list *tunnel) { struct sk_buff *skb; skb = amt_build_igmp_gq(amt); if (!skb) return; amt_skb_cb(skb)->tunnel = tunnel; dev_queue_xmit(skb); } #if IS_ENABLED(CONFIG_IPV6) static struct sk_buff *amt_build_mld_gq(struct amt_dev *amt) { u8 ra[AMT_IP6HDR_OPTS] = { IPPROTO_ICMPV6, 0, IPV6_TLV_ROUTERALERT, 2, 0, 0, IPV6_TLV_PAD1, IPV6_TLV_PAD1 }; int hlen = LL_RESERVED_SPACE(amt->dev); int tlen = amt->dev->needed_tailroom; struct mld2_query *mld2q; void *csum_start = NULL; struct ipv6hdr *ip6h; struct sk_buff *skb; struct ethhdr *eth; u32 len; len = hlen + tlen + sizeof(*ip6h) + sizeof(ra) + sizeof(*mld2q); skb = netdev_alloc_skb_ip_align(amt->dev, len); if (!skb) return NULL; skb_reserve(skb, hlen); skb_push(skb, sizeof(*eth)); skb_reset_mac_header(skb); eth = eth_hdr(skb); skb->priority = TC_PRIO_CONTROL; skb->protocol = htons(ETH_P_IPV6); skb_put_zero(skb, sizeof(*ip6h)); skb_put_data(skb, ra, sizeof(ra)); skb_put_zero(skb, sizeof(*mld2q)); skb_pull(skb, sizeof(*eth)); skb_reset_network_header(skb); ip6h = ipv6_hdr(skb); ip6h->payload_len = htons(sizeof(ra) + sizeof(*mld2q)); ip6h->nexthdr = NEXTHDR_HOP; ip6h->hop_limit = 1; ip6h->daddr = mld2_all_node; ip6_flow_hdr(ip6h, 0, 0); if (ipv6_dev_get_saddr(amt->net, amt->dev, &ip6h->daddr, 0, &ip6h->saddr)) { amt->dev->stats.tx_errors++; kfree_skb(skb); return NULL; } eth->h_proto = htons(ETH_P_IPV6); ether_addr_copy(eth->h_source, amt->dev->dev_addr); ipv6_eth_mc_map(&mld2_all_node, eth->h_dest); skb_pull(skb, sizeof(*ip6h) + sizeof(ra)); skb_reset_transport_header(skb); mld2q = (struct mld2_query *)icmp6_hdr(skb); mld2q->mld2q_mrc = htons(1); mld2q->mld2q_type = ICMPV6_MGM_QUERY; mld2q->mld2q_code = 0; mld2q->mld2q_cksum = 0; mld2q->mld2q_resv1 = 0; mld2q->mld2q_resv2 = 0; mld2q->mld2q_suppress = 0; mld2q->mld2q_qrv = amt->qrv; mld2q->mld2q_nsrcs = 0; mld2q->mld2q_qqic = amt->qi; csum_start = (void *)mld2q; mld2q->mld2q_cksum = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, sizeof(*mld2q), IPPROTO_ICMPV6, csum_partial(csum_start, sizeof(*mld2q), 0)); skb->ip_summed = CHECKSUM_NONE; skb_push(skb, sizeof(*eth) + sizeof(*ip6h) + sizeof(ra)); return skb; } static void amt_send_mld_gq(struct amt_dev *amt, struct amt_tunnel_list *tunnel) { struct sk_buff *skb; skb = amt_build_mld_gq(amt); if (!skb) return; amt_skb_cb(skb)->tunnel = tunnel; dev_queue_xmit(skb); } #else static void amt_send_mld_gq(struct amt_dev *amt, struct amt_tunnel_list *tunnel) { } #endif static bool amt_queue_event(struct amt_dev *amt, enum amt_event event, struct sk_buff *skb) { int index; spin_lock_bh(&amt->lock); if (amt->nr_events >= AMT_MAX_EVENTS) { spin_unlock_bh(&amt->lock); return 1; } index = (amt->event_idx + amt->nr_events) % AMT_MAX_EVENTS; amt->events[index].event = event; amt->events[index].skb = skb; amt->nr_events++; amt->event_idx %= AMT_MAX_EVENTS; queue_work(amt_wq, &amt->event_wq); spin_unlock_bh(&amt->lock); return 0; } static void amt_secret_work(struct work_struct *work) { struct amt_dev *amt = container_of(to_delayed_work(work), struct amt_dev, secret_wq); spin_lock_bh(&amt->lock); get_random_bytes(&amt->key, sizeof(siphash_key_t)); spin_unlock_bh(&amt->lock); mod_delayed_work(amt_wq, &amt->secret_wq, msecs_to_jiffies(AMT_SECRET_TIMEOUT)); } static void amt_event_send_discovery(struct amt_dev *amt) { if (amt->status > AMT_STATUS_SENT_DISCOVERY) goto out; get_random_bytes(&amt->nonce, sizeof(__be32)); amt_send_discovery(amt); out: mod_delayed_work(amt_wq, &amt->discovery_wq, msecs_to_jiffies(AMT_DISCOVERY_TIMEOUT)); } static void amt_discovery_work(struct work_struct *work) { struct amt_dev *amt = container_of(to_delayed_work(work), struct amt_dev, discovery_wq); if (amt_queue_event(amt, AMT_EVENT_SEND_DISCOVERY, NULL)) mod_delayed_work(amt_wq, &amt->discovery_wq, msecs_to_jiffies(AMT_DISCOVERY_TIMEOUT)); } static void amt_event_send_request(struct amt_dev *amt) { u32 exp; if (amt->status < AMT_STATUS_RECEIVED_ADVERTISEMENT) goto out; if (amt->req_cnt > AMT_MAX_REQ_COUNT) { netdev_dbg(amt->dev, "Gateway is not ready"); amt->qi = AMT_INIT_REQ_TIMEOUT; WRITE_ONCE(amt->ready4, false); WRITE_ONCE(amt->ready6, false); amt->remote_ip = 0; amt_update_gw_status(amt, AMT_STATUS_INIT, false); amt->req_cnt = 0; amt->nonce = 0; goto out; } if (!amt->req_cnt) { WRITE_ONCE(amt->ready4, false); WRITE_ONCE(amt->ready6, false); get_random_bytes(&amt->nonce, sizeof(__be32)); } amt_send_request(amt, false); amt_send_request(amt, true); amt_update_gw_status(amt, AMT_STATUS_SENT_REQUEST, true); amt->req_cnt++; out: exp = min_t(u32, (1 * (1 << amt->req_cnt)), AMT_MAX_REQ_TIMEOUT); mod_delayed_work(amt_wq, &amt->req_wq, msecs_to_jiffies(exp * 1000)); } static void amt_req_work(struct work_struct *work) { struct amt_dev *amt = container_of(to_delayed_work(work), struct amt_dev, req_wq); if (amt_queue_event(amt, AMT_EVENT_SEND_REQUEST, NULL)) mod_delayed_work(amt_wq, &amt->req_wq, msecs_to_jiffies(100)); } static bool amt_send_membership_update(struct amt_dev *amt, struct sk_buff *skb, bool v6) { struct amt_header_membership_update *amtmu; struct socket *sock; struct iphdr *iph; struct flowi4 fl4; struct rtable *rt; int err; sock = rcu_dereference_bh(amt->sock); if (!sock) return true; err = skb_cow_head(skb, LL_RESERVED_SPACE(amt->dev) + sizeof(*amtmu) + sizeof(*iph) + sizeof(struct udphdr)); if (err) return true; skb_reset_inner_headers(skb); memset(&fl4, 0, sizeof(struct flowi4)); fl4.flowi4_oif = amt->stream_dev->ifindex; fl4.daddr = amt->remote_ip; fl4.saddr = amt->local_ip; fl4.flowi4_tos = AMT_TOS; fl4.flowi4_proto = IPPROTO_UDP; rt = ip_route_output_key(amt->net, &fl4); if (IS_ERR(rt)) { netdev_dbg(amt->dev, "no route to %pI4\n", &amt->remote_ip); return true; } amtmu = skb_push(skb, sizeof(*amtmu)); amtmu->version = 0; amtmu->type = AMT_MSG_MEMBERSHIP_UPDATE; amtmu->reserved = 0; amtmu->nonce = amt->nonce; amtmu->response_mac = amt->mac; if (!v6) skb_set_inner_protocol(skb, htons(ETH_P_IP)); else skb_set_inner_protocol(skb, htons(ETH_P_IPV6)); udp_tunnel_xmit_skb(rt, sock->sk, skb, fl4.saddr, fl4.daddr, AMT_TOS, ip4_dst_hoplimit(&rt->dst), 0, amt->gw_port, amt->relay_port, false, false); amt_update_gw_status(amt, AMT_STATUS_SENT_UPDATE, true); return false; } static void amt_send_multicast_data(struct amt_dev *amt, const struct sk_buff *oskb, struct amt_tunnel_list *tunnel, bool v6) { struct amt_header_mcast_data *amtmd; struct socket *sock; struct sk_buff *skb; struct iphdr *iph; struct flowi4 fl4; struct rtable *rt; sock = rcu_dereference_bh(amt->sock); if (!sock) return; skb = skb_copy_expand(oskb, sizeof(*amtmd) + sizeof(*iph) + sizeof(struct udphdr), 0, GFP_ATOMIC); if (!skb) return; skb_reset_inner_headers(skb); memset(&fl4, 0, sizeof(struct flowi4)); fl4.flowi4_oif = amt->stream_dev->ifindex; fl4.daddr = tunnel->ip4; fl4.saddr = amt->local_ip; fl4.flowi4_proto = IPPROTO_UDP; rt = ip_route_output_key(amt->net, &fl4); if (IS_ERR(rt)) { netdev_dbg(amt->dev, "no route to %pI4\n", &tunnel->ip4); kfree_skb(skb); return; } amtmd = skb_push(skb, sizeof(*amtmd)); amtmd->version = 0; amtmd->reserved = 0; amtmd->type = AMT_MSG_MULTICAST_DATA; if (!v6) skb_set_inner_protocol(skb, htons(ETH_P_IP)); else skb_set_inner_protocol(skb, htons(ETH_P_IPV6)); udp_tunnel_xmit_skb(rt, sock->sk, skb, fl4.saddr, fl4.daddr, AMT_TOS, ip4_dst_hoplimit(&rt->dst), 0, amt->relay_port, tunnel->source_port, false, false); } static bool amt_send_membership_query(struct amt_dev *amt, struct sk_buff *skb, struct amt_tunnel_list *tunnel, bool v6) { struct amt_header_membership_query *amtmq; struct socket *sock; struct rtable *rt; struct flowi4 fl4; int err; sock = rcu_dereference_bh(amt->sock); if (!sock) return true; err = skb_cow_head(skb, LL_RESERVED_SPACE(amt->dev) + sizeof(*amtmq) + sizeof(struct iphdr) + sizeof(struct udphdr)); if (err) return true; skb_reset_inner_headers(skb); memset(&fl4, 0, sizeof(struct flowi4)); fl4.flowi4_oif = amt->stream_dev->ifindex; fl4.daddr = tunnel->ip4; fl4.saddr = amt->local_ip; fl4.flowi4_tos = AMT_TOS; fl4.flowi4_proto = IPPROTO_UDP; rt = ip_route_output_key(amt->net, &fl4); if (IS_ERR(rt)) { netdev_dbg(amt->dev, "no route to %pI4\n", &tunnel->ip4); return true; } amtmq = skb_push(skb, sizeof(*amtmq)); amtmq->version = 0; amtmq->type = AMT_MSG_MEMBERSHIP_QUERY; amtmq->reserved = 0; amtmq->l = 0; amtmq->g = 0; amtmq->nonce = tunnel->nonce; amtmq->response_mac = tunnel->mac; if (!v6) skb_set_inner_protocol(skb, htons(ETH_P_IP)); else skb_set_inner_protocol(skb, htons(ETH_P_IPV6)); udp_tunnel_xmit_skb(rt, sock->sk, skb, fl4.saddr, fl4.daddr, AMT_TOS, ip4_dst_hoplimit(&rt->dst), 0, amt->relay_port, tunnel->source_port, false, false); amt_update_relay_status(tunnel, AMT_STATUS_SENT_QUERY, true); return false; } static netdev_tx_t amt_dev_xmit(struct sk_buff *skb, struct net_device *dev) { struct amt_dev *amt = netdev_priv(dev); struct amt_tunnel_list *tunnel; struct amt_group_node *gnode; union amt_addr group = {0,}; #if IS_ENABLED(CONFIG_IPV6) struct ipv6hdr *ip6h; struct mld_msg *mld; #endif bool report = false; struct igmphdr *ih; bool query = false; struct iphdr *iph; bool data = false; bool v6 = false; u32 hash; iph = ip_hdr(skb); if (iph->version == 4) { if (!ipv4_is_multicast(iph->daddr)) goto free; if (!ip_mc_check_igmp(skb)) { ih = igmp_hdr(skb); switch (ih->type) { case IGMPV3_HOST_MEMBERSHIP_REPORT: case IGMP_HOST_MEMBERSHIP_REPORT: report = true; break; case IGMP_HOST_MEMBERSHIP_QUERY: query = true; break; default: goto free; } } else { data = true; } v6 = false; group.ip4 = iph->daddr; #if IS_ENABLED(CONFIG_IPV6) } else if (iph->version == 6) { ip6h = ipv6_hdr(skb); if (!ipv6_addr_is_multicast(&ip6h->daddr)) goto free; if (!ipv6_mc_check_mld(skb)) { mld = (struct mld_msg *)skb_transport_header(skb); switch (mld->mld_type) { case ICMPV6_MGM_REPORT: case ICMPV6_MLD2_REPORT: report = true; break; case ICMPV6_MGM_QUERY: query = true; break; default: goto free; } } else { data = true; } v6 = true; group.ip6 = ip6h->daddr; #endif } else { dev->stats.tx_errors++; goto free; } if (!pskb_may_pull(skb, sizeof(struct ethhdr))) goto free; skb_pull(skb, sizeof(struct ethhdr)); if (amt->mode == AMT_MODE_GATEWAY) { /* Gateway only passes IGMP/MLD packets */ if (!report) goto free; if ((!v6 && !READ_ONCE(amt->ready4)) || (v6 && !READ_ONCE(amt->ready6))) goto free; if (amt_send_membership_update(amt, skb, v6)) goto free; goto unlock; } else if (amt->mode == AMT_MODE_RELAY) { if (query) { tunnel = amt_skb_cb(skb)->tunnel; if (!tunnel) { WARN_ON(1); goto free; } /* Do not forward unexpected query */ if (amt_send_membership_query(amt, skb, tunnel, v6)) goto free; goto unlock; } if (!data) goto free; list_for_each_entry_rcu(tunnel, &amt->tunnel_list, list) { hash = amt_group_hash(tunnel, &group); hlist_for_each_entry_rcu(gnode, &tunnel->groups[hash], node) { if (!v6) { if (gnode->group_addr.ip4 == iph->daddr) goto found; #if IS_ENABLED(CONFIG_IPV6) } else { if (ipv6_addr_equal(&gnode->group_addr.ip6, &ip6h->daddr)) goto found; #endif } } continue; found: amt_send_multicast_data(amt, skb, tunnel, v6); } } dev_kfree_skb(skb); return NETDEV_TX_OK; free: dev_kfree_skb(skb); unlock: dev->stats.tx_dropped++; return NETDEV_TX_OK; } static int amt_parse_type(struct sk_buff *skb) { struct amt_header *amth; if (!pskb_may_pull(skb, sizeof(struct udphdr) + sizeof(struct amt_header))) return -1; amth = (struct amt_header *)(udp_hdr(skb) + 1); if (amth->version != 0) return -1; if (amth->type >= __AMT_MSG_MAX || !amth->type) return -1; return amth->type; } static void amt_clear_groups(struct amt_tunnel_list *tunnel) { struct amt_dev *amt = tunnel->amt; struct amt_group_node *gnode; struct hlist_node *t; int i; spin_lock_bh(&tunnel->lock); rcu_read_lock(); for (i = 0; i < amt->hash_buckets; i++) hlist_for_each_entry_safe(gnode, t, &tunnel->groups[i], node) amt_del_group(amt, gnode); rcu_read_unlock(); spin_unlock_bh(&tunnel->lock); } static void amt_tunnel_expire(struct work_struct *work) { struct amt_tunnel_list *tunnel = container_of(to_delayed_work(work), struct amt_tunnel_list, gc_wq); struct amt_dev *amt = tunnel->amt; spin_lock_bh(&amt->lock); rcu_read_lock(); list_del_rcu(&tunnel->list); amt->nr_tunnels--; amt_clear_groups(tunnel); rcu_read_unlock(); spin_unlock_bh(&amt->lock); kfree_rcu(tunnel, rcu); } static void amt_cleanup_srcs(struct amt_dev *amt, struct amt_tunnel_list *tunnel, struct amt_group_node *gnode) { struct amt_source_node *snode; struct hlist_node *t; int i; /* Delete old sources */ for (i = 0; i < amt->hash_buckets; i++) { hlist_for_each_entry_safe(snode, t, &gnode->sources[i], node) { if (snode->flags == AMT_SOURCE_OLD) amt_destroy_source(snode); } } /* switch from new to old */ for (i = 0; i < amt->hash_buckets; i++) { hlist_for_each_entry_rcu(snode, &gnode->sources[i], node) { snode->flags = AMT_SOURCE_OLD; if (!gnode->v6) netdev_dbg(snode->gnode->amt->dev, "Add source as OLD %pI4 from %pI4\n", &snode->source_addr.ip4, &gnode->group_addr.ip4); #if IS_ENABLED(CONFIG_IPV6) else netdev_dbg(snode->gnode->amt->dev, "Add source as OLD %pI6 from %pI6\n", &snode->source_addr.ip6, &gnode->group_addr.ip6); #endif } } } static void amt_add_srcs(struct amt_dev *amt, struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, void *grec, bool v6) { struct igmpv3_grec *igmp_grec; struct amt_source_node *snode; #if IS_ENABLED(CONFIG_IPV6) struct mld2_grec *mld_grec; #endif union amt_addr src = {0,}; u16 nsrcs; u32 hash; int i; if (!v6) { igmp_grec = grec; nsrcs = ntohs(igmp_grec->grec_nsrcs); } else { #if IS_ENABLED(CONFIG_IPV6) mld_grec = grec; nsrcs = ntohs(mld_grec->grec_nsrcs); #else return; #endif } for (i = 0; i < nsrcs; i++) { if (tunnel->nr_sources >= amt->max_sources) return; if (!v6) src.ip4 = igmp_grec->grec_src[i]; #if IS_ENABLED(CONFIG_IPV6) else memcpy(&src.ip6, &mld_grec->grec_src[i], sizeof(struct in6_addr)); #endif if (amt_lookup_src(tunnel, gnode, AMT_FILTER_ALL, &src)) continue; snode = amt_alloc_snode(gnode, &src); if (snode) { hash = amt_source_hash(tunnel, &snode->source_addr); hlist_add_head_rcu(&snode->node, &gnode->sources[hash]); tunnel->nr_sources++; gnode->nr_sources++; if (!gnode->v6) netdev_dbg(snode->gnode->amt->dev, "Add source as NEW %pI4 from %pI4\n", &snode->source_addr.ip4, &gnode->group_addr.ip4); #if IS_ENABLED(CONFIG_IPV6) else netdev_dbg(snode->gnode->amt->dev, "Add source as NEW %pI6 from %pI6\n", &snode->source_addr.ip6, &gnode->group_addr.ip6); #endif } } } /* Router State Report Rec'd New Router State * ------------ ------------ ---------------- * EXCLUDE (X,Y) IS_IN (A) EXCLUDE (X+A,Y-A) * * -----------+-----------+-----------+ * | OLD | NEW | * -----------+-----------+-----------+ * FWD | X | X+A | * -----------+-----------+-----------+ * D_FWD | Y | Y-A | * -----------+-----------+-----------+ * NONE | | A | * -----------+-----------+-----------+ * * a) Received sources are NONE/NEW * b) All NONE will be deleted by amt_cleanup_srcs(). * c) All OLD will be deleted by amt_cleanup_srcs(). * d) After delete, NEW source will be switched to OLD. */ static void amt_lookup_act_srcs(struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, void *grec, enum amt_ops ops, enum amt_filter filter, enum amt_act act, bool v6) { struct amt_dev *amt = tunnel->amt; struct amt_source_node *snode; struct igmpv3_grec *igmp_grec; #if IS_ENABLED(CONFIG_IPV6) struct mld2_grec *mld_grec; #endif union amt_addr src = {0,}; struct hlist_node *t; u16 nsrcs; int i, j; if (!v6) { igmp_grec = grec; nsrcs = ntohs(igmp_grec->grec_nsrcs); } else { #if IS_ENABLED(CONFIG_IPV6) mld_grec = grec; nsrcs = ntohs(mld_grec->grec_nsrcs); #else return; #endif } memset(&src, 0, sizeof(union amt_addr)); switch (ops) { case AMT_OPS_INT: /* A*B */ for (i = 0; i < nsrcs; i++) { if (!v6) src.ip4 = igmp_grec->grec_src[i]; #if IS_ENABLED(CONFIG_IPV6) else memcpy(&src.ip6, &mld_grec->grec_src[i], sizeof(struct in6_addr)); #endif snode = amt_lookup_src(tunnel, gnode, filter, &src); if (!snode) continue; amt_act_src(tunnel, gnode, snode, act); } break; case AMT_OPS_UNI: /* A+B */ for (i = 0; i < amt->hash_buckets; i++) { hlist_for_each_entry_safe(snode, t, &gnode->sources[i], node) { if (amt_status_filter(snode, filter)) amt_act_src(tunnel, gnode, snode, act); } } for (i = 0; i < nsrcs; i++) { if (!v6) src.ip4 = igmp_grec->grec_src[i]; #if IS_ENABLED(CONFIG_IPV6) else memcpy(&src.ip6, &mld_grec->grec_src[i], sizeof(struct in6_addr)); #endif snode = amt_lookup_src(tunnel, gnode, filter, &src); if (!snode) continue; amt_act_src(tunnel, gnode, snode, act); } break; case AMT_OPS_SUB: /* A-B */ for (i = 0; i < amt->hash_buckets; i++) { hlist_for_each_entry_safe(snode, t, &gnode->sources[i], node) { if (!amt_status_filter(snode, filter)) continue; for (j = 0; j < nsrcs; j++) { if (!v6) src.ip4 = igmp_grec->grec_src[j]; #if IS_ENABLED(CONFIG_IPV6) else memcpy(&src.ip6, &mld_grec->grec_src[j], sizeof(struct in6_addr)); #endif if (amt_addr_equal(&snode->source_addr, &src)) goto out_sub; } amt_act_src(tunnel, gnode, snode, act); continue; out_sub:; } } break; case AMT_OPS_SUB_REV: /* B-A */ for (i = 0; i < nsrcs; i++) { if (!v6) src.ip4 = igmp_grec->grec_src[i]; #if IS_ENABLED(CONFIG_IPV6) else memcpy(&src.ip6, &mld_grec->grec_src[i], sizeof(struct in6_addr)); #endif snode = amt_lookup_src(tunnel, gnode, AMT_FILTER_ALL, &src); if (!snode) { snode = amt_lookup_src(tunnel, gnode, filter, &src); if (snode) amt_act_src(tunnel, gnode, snode, act); } } break; default: netdev_dbg(amt->dev, "Invalid type\n"); return; } } static void amt_mcast_is_in_handler(struct amt_dev *amt, struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, void *grec, void *zero_grec, bool v6) { if (gnode->filter_mode == MCAST_INCLUDE) { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * INCLUDE (A) IS_IN (B) INCLUDE (A+B) (B)=GMI */ /* Update IS_IN (B) as FWD/NEW */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_NONE_NEW, AMT_ACT_STATUS_FWD_NEW, v6); /* Update INCLUDE (A) as NEW */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* (B)=GMI */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_FWD_NEW, AMT_ACT_GMI, v6); } else { /* State Actions * ------------ ------------ ---------------- ------- * EXCLUDE (X,Y) IS_IN (A) EXCLUDE (X+A,Y-A) (A)=GMI */ /* Update (A) in (X, Y) as NONE/NEW */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_BOTH, AMT_ACT_STATUS_NONE_NEW, v6); /* Update FWD/OLD as FWD/NEW */ amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* Update IS_IN (A) as FWD/NEW */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_NONE_NEW, AMT_ACT_STATUS_FWD_NEW, v6); /* Update EXCLUDE (, Y-A) as D_FWD_NEW */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB, AMT_FILTER_D_FWD, AMT_ACT_STATUS_D_FWD_NEW, v6); } } static void amt_mcast_is_ex_handler(struct amt_dev *amt, struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, void *grec, void *zero_grec, bool v6) { if (gnode->filter_mode == MCAST_INCLUDE) { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * INCLUDE (A) IS_EX (B) EXCLUDE (A*B,B-A) (B-A)=0 * Delete (A-B) * Group Timer=GMI */ /* EXCLUDE(A*B, ) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* EXCLUDE(, B-A) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV, AMT_FILTER_FWD, AMT_ACT_STATUS_D_FWD_NEW, v6); /* (B-A)=0 */ amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI, AMT_FILTER_D_FWD_NEW, AMT_ACT_GMI_ZERO, v6); /* Group Timer=GMI */ if (!mod_delayed_work(amt_wq, &gnode->group_timer, msecs_to_jiffies(amt_gmi(amt)))) dev_hold(amt->dev); gnode->filter_mode = MCAST_EXCLUDE; /* Delete (A-B) will be worked by amt_cleanup_srcs(). */ } else { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * EXCLUDE (X,Y) IS_EX (A) EXCLUDE (A-Y,Y*A) (A-X-Y)=GMI * Delete (X-A) * Delete (Y-A) * Group Timer=GMI */ /* EXCLUDE (A-Y, ) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV, AMT_FILTER_D_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* EXCLUDE (, Y*A ) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_D_FWD, AMT_ACT_STATUS_D_FWD_NEW, v6); /* (A-X-Y)=GMI */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV, AMT_FILTER_BOTH_NEW, AMT_ACT_GMI, v6); /* Group Timer=GMI */ if (!mod_delayed_work(amt_wq, &gnode->group_timer, msecs_to_jiffies(amt_gmi(amt)))) dev_hold(amt->dev); /* Delete (X-A), (Y-A) will be worked by amt_cleanup_srcs(). */ } } static void amt_mcast_to_in_handler(struct amt_dev *amt, struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, void *grec, void *zero_grec, bool v6) { if (gnode->filter_mode == MCAST_INCLUDE) { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * INCLUDE (A) TO_IN (B) INCLUDE (A+B) (B)=GMI * Send Q(G,A-B) */ /* Update TO_IN (B) sources as FWD/NEW */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_NONE_NEW, AMT_ACT_STATUS_FWD_NEW, v6); /* Update INCLUDE (A) sources as NEW */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* (B)=GMI */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_FWD_NEW, AMT_ACT_GMI, v6); } else { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * EXCLUDE (X,Y) TO_IN (A) EXCLUDE (X+A,Y-A) (A)=GMI * Send Q(G,X-A) * Send Q(G) */ /* Update TO_IN (A) sources as FWD/NEW */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_NONE_NEW, AMT_ACT_STATUS_FWD_NEW, v6); /* Update EXCLUDE(X,) sources as FWD/NEW */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* EXCLUDE (, Y-A) * (A) are already switched to FWD_NEW. * So, D_FWD/OLD -> D_FWD/NEW is okay. */ amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI, AMT_FILTER_D_FWD, AMT_ACT_STATUS_D_FWD_NEW, v6); /* (A)=GMI * Only FWD_NEW will have (A) sources. */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_FWD_NEW, AMT_ACT_GMI, v6); } } static void amt_mcast_to_ex_handler(struct amt_dev *amt, struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, void *grec, void *zero_grec, bool v6) { if (gnode->filter_mode == MCAST_INCLUDE) { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * INCLUDE (A) TO_EX (B) EXCLUDE (A*B,B-A) (B-A)=0 * Delete (A-B) * Send Q(G,A*B) * Group Timer=GMI */ /* EXCLUDE (A*B, ) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* EXCLUDE (, B-A) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV, AMT_FILTER_FWD, AMT_ACT_STATUS_D_FWD_NEW, v6); /* (B-A)=0 */ amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI, AMT_FILTER_D_FWD_NEW, AMT_ACT_GMI_ZERO, v6); /* Group Timer=GMI */ if (!mod_delayed_work(amt_wq, &gnode->group_timer, msecs_to_jiffies(amt_gmi(amt)))) dev_hold(amt->dev); gnode->filter_mode = MCAST_EXCLUDE; /* Delete (A-B) will be worked by amt_cleanup_srcs(). */ } else { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * EXCLUDE (X,Y) TO_EX (A) EXCLUDE (A-Y,Y*A) (A-X-Y)=Group Timer * Delete (X-A) * Delete (Y-A) * Send Q(G,A-Y) * Group Timer=GMI */ /* Update (A-X-Y) as NONE/OLD */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV, AMT_FILTER_BOTH, AMT_ACT_GT, v6); /* EXCLUDE (A-Y, ) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV, AMT_FILTER_D_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* EXCLUDE (, Y*A) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_D_FWD, AMT_ACT_STATUS_D_FWD_NEW, v6); /* Group Timer=GMI */ if (!mod_delayed_work(amt_wq, &gnode->group_timer, msecs_to_jiffies(amt_gmi(amt)))) dev_hold(amt->dev); /* Delete (X-A), (Y-A) will be worked by amt_cleanup_srcs(). */ } } static void amt_mcast_allow_handler(struct amt_dev *amt, struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, void *grec, void *zero_grec, bool v6) { if (gnode->filter_mode == MCAST_INCLUDE) { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * INCLUDE (A) ALLOW (B) INCLUDE (A+B) (B)=GMI */ /* INCLUDE (A+B) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* (B)=GMI */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_FWD_NEW, AMT_ACT_GMI, v6); } else { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * EXCLUDE (X,Y) ALLOW (A) EXCLUDE (X+A,Y-A) (A)=GMI */ /* EXCLUDE (X+A, ) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* EXCLUDE (, Y-A) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB, AMT_FILTER_D_FWD, AMT_ACT_STATUS_D_FWD_NEW, v6); /* (A)=GMI * All (A) source are now FWD/NEW status. */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_INT, AMT_FILTER_FWD_NEW, AMT_ACT_GMI, v6); } } static void amt_mcast_block_handler(struct amt_dev *amt, struct amt_tunnel_list *tunnel, struct amt_group_node *gnode, void *grec, void *zero_grec, bool v6) { if (gnode->filter_mode == MCAST_INCLUDE) { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * INCLUDE (A) BLOCK (B) INCLUDE (A) Send Q(G,A*B) */ /* INCLUDE (A) */ amt_lookup_act_srcs(tunnel, gnode, zero_grec, AMT_OPS_UNI, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); } else { /* Router State Report Rec'd New Router State Actions * ------------ ------------ ---------------- ------- * EXCLUDE (X,Y) BLOCK (A) EXCLUDE (X+(A-Y),Y) (A-X-Y)=Group Timer * Send Q(G,A-Y) */ /* (A-X-Y)=Group Timer */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV, AMT_FILTER_BOTH, AMT_ACT_GT, v6); /* EXCLUDE (X, ) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* EXCLUDE (X+(A-Y) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_SUB_REV, AMT_FILTER_D_FWD, AMT_ACT_STATUS_FWD_NEW, v6); /* EXCLUDE (, Y) */ amt_lookup_act_srcs(tunnel, gnode, grec, AMT_OPS_UNI, AMT_FILTER_D_FWD, AMT_ACT_STATUS_D_FWD_NEW, v6); } } /* RFC 3376 * 7.3.2. In the Presence of Older Version Group Members * * When Group Compatibility Mode is IGMPv2, a router internally * translates the following IGMPv2 messages for that group to their * IGMPv3 equivalents: * * IGMPv2 Message IGMPv3 Equivalent * -------------- ----------------- * Report IS_EX( {} ) * Leave TO_IN( {} ) */ static void amt_igmpv2_report_handler(struct amt_dev *amt, struct sk_buff *skb, struct amt_tunnel_list *tunnel) { struct igmphdr *ih = igmp_hdr(skb); struct iphdr *iph = ip_hdr(skb); struct amt_group_node *gnode; union amt_addr group, host; memset(&group, 0, sizeof(union amt_addr)); group.ip4 = ih->group; memset(&host, 0, sizeof(union amt_addr)); host.ip4 = iph->saddr; gnode = amt_lookup_group(tunnel, &group, &host, false); if (!gnode) { gnode = amt_add_group(amt, tunnel, &group, &host, false); if (!IS_ERR(gnode)) { gnode->filter_mode = MCAST_EXCLUDE; if (!mod_delayed_work(amt_wq, &gnode->group_timer, msecs_to_jiffies(amt_gmi(amt)))) dev_hold(amt->dev); } } } /* RFC 3376 * 7.3.2. In the Presence of Older Version Group Members * * When Group Compatibility Mode is IGMPv2, a router internally * translates the following IGMPv2 messages for that group to their * IGMPv3 equivalents: * * IGMPv2 Message IGMPv3 Equivalent * -------------- ----------------- * Report IS_EX( {} ) * Leave TO_IN( {} ) */ static void amt_igmpv2_leave_handler(struct amt_dev *amt, struct sk_buff *skb, struct amt_tunnel_list *tunnel) { struct igmphdr *ih = igmp_hdr(skb); struct iphdr *iph = ip_hdr(skb); struct amt_group_node *gnode; union amt_addr group, host; memset(&group, 0, sizeof(union amt_addr)); group.ip4 = ih->group; memset(&host, 0, sizeof(union amt_addr)); host.ip4 = iph->saddr; gnode = amt_lookup_group(tunnel, &group, &host, false); if (gnode) amt_del_group(amt, gnode); } static void amt_igmpv3_report_handler(struct amt_dev *amt, struct sk_buff *skb, struct amt_tunnel_list *tunnel) { struct igmpv3_report *ihrv3 = igmpv3_report_hdr(skb); int len = skb_transport_offset(skb) + sizeof(*ihrv3); void *zero_grec = (void *)&igmpv3_zero_grec; struct iphdr *iph = ip_hdr(skb); struct amt_group_node *gnode; union amt_addr group, host; struct igmpv3_grec *grec; u16 nsrcs; int i; for (i = 0; i < ntohs(ihrv3->ngrec); i++) { len += sizeof(*grec); if (!ip_mc_may_pull(skb, len)) break; grec = (void *)(skb->data + len - sizeof(*grec)); nsrcs = ntohs(grec->grec_nsrcs); len += nsrcs * sizeof(__be32); if (!ip_mc_may_pull(skb, len)) break; memset(&group, 0, sizeof(union amt_addr)); group.ip4 = grec->grec_mca; memset(&host, 0, sizeof(union amt_addr)); host.ip4 = iph->saddr; gnode = amt_lookup_group(tunnel, &group, &host, false); if (!gnode) { gnode = amt_add_group(amt, tunnel, &group, &host, false); if (IS_ERR(gnode)) continue; } amt_add_srcs(amt, tunnel, gnode, grec, false); switch (grec->grec_type) { case IGMPV3_MODE_IS_INCLUDE: amt_mcast_is_in_handler(amt, tunnel, gnode, grec, zero_grec, false); break; case IGMPV3_MODE_IS_EXCLUDE: amt_mcast_is_ex_handler(amt, tunnel, gnode, grec, zero_grec, false); break; case IGMPV3_CHANGE_TO_INCLUDE: amt_mcast_to_in_handler(amt, tunnel, gnode, grec, zero_grec, false); break; case IGMPV3_CHANGE_TO_EXCLUDE: amt_mcast_to_ex_handler(amt, tunnel, gnode, grec, zero_grec, false); break; case IGMPV3_ALLOW_NEW_SOURCES: amt_mcast_allow_handler(amt, tunnel, gnode, grec, zero_grec, false); break; case IGMPV3_BLOCK_OLD_SOURCES: amt_mcast_block_handler(amt, tunnel, gnode, grec, zero_grec, false); break; default: break; } amt_cleanup_srcs(amt, tunnel, gnode); } } /* caller held tunnel->lock */ static void amt_igmp_report_handler(struct amt_dev *amt, struct sk_buff *skb, struct amt_tunnel_list *tunnel) { struct igmphdr *ih = igmp_hdr(skb); switch (ih->type) { case IGMPV3_HOST_MEMBERSHIP_REPORT: amt_igmpv3_report_handler(amt, skb, tunnel); break; case IGMPV2_HOST_MEMBERSHIP_REPORT: amt_igmpv2_report_handler(amt, skb, tunnel); break; case IGMP_HOST_LEAVE_MESSAGE: amt_igmpv2_leave_handler(amt, skb, tunnel); break; default: break; } } #if IS_ENABLED(CONFIG_IPV6) /* RFC 3810 * 8.3.2. In the Presence of MLDv1 Multicast Address Listeners * * When Multicast Address Compatibility Mode is MLDv2, a router acts * using the MLDv2 protocol for that multicast address. When Multicast * Address Compatibility Mode is MLDv1, a router internally translates * the following MLDv1 messages for that multicast address to their * MLDv2 equivalents: * * MLDv1 Message MLDv2 Equivalent * -------------- ----------------- * Report IS_EX( {} ) * Done TO_IN( {} ) */ static void amt_mldv1_report_handler(struct amt_dev *amt, struct sk_buff *skb, struct amt_tunnel_list *tunnel) { struct mld_msg *mld = (struct mld_msg *)icmp6_hdr(skb); struct ipv6hdr *ip6h = ipv6_hdr(skb); struct amt_group_node *gnode; union amt_addr group, host; memcpy(&group.ip6, &mld->mld_mca, sizeof(struct in6_addr)); memcpy(&host.ip6, &ip6h->saddr, sizeof(struct in6_addr)); gnode = amt_lookup_group(tunnel, &group, &host, true); if (!gnode) { gnode = amt_add_group(amt, tunnel, &group, &host, true); if (!IS_ERR(gnode)) { gnode->filter_mode = MCAST_EXCLUDE; if (!mod_delayed_work(amt_wq, &gnode->group_timer, msecs_to_jiffies(amt_gmi(amt)))) dev_hold(amt->dev); } } } /* RFC 3810 * 8.3.2. In the Presence of MLDv1 Multicast Address Listeners * * When Multicast Address Compatibility Mode is MLDv2, a router acts * using the MLDv2 protocol for that multicast address. When Multicast * Address Compatibility Mode is MLDv1, a router internally translates * the following MLDv1 messages for that multicast address to their * MLDv2 equivalents: * * MLDv1 Message MLDv2 Equivalent * -------------- ----------------- * Report IS_EX( {} ) * Done TO_IN( {} ) */ static void amt_mldv1_leave_handler(struct amt_dev *amt, struct sk_buff *skb, struct amt_tunnel_list *tunnel) { struct mld_msg *mld = (struct mld_msg *)icmp6_hdr(skb); struct iphdr *iph = ip_hdr(skb); struct amt_group_node *gnode; union amt_addr group, host; memcpy(&group.ip6, &mld->mld_mca, sizeof(struct in6_addr)); memset(&host, 0, sizeof(union amt_addr)); host.ip4 = iph->saddr; gnode = amt_lookup_group(tunnel, &group, &host, true); if (gnode) { amt_del_group(amt, gnode); return; } } static void amt_mldv2_report_handler(struct amt_dev *amt, struct sk_buff *skb, struct amt_tunnel_list *tunnel) { struct mld2_report *mld2r = (struct mld2_report *)icmp6_hdr(skb); int len = skb_transport_offset(skb) + sizeof(*mld2r); void *zero_grec = (void *)&mldv2_zero_grec; struct ipv6hdr *ip6h = ipv6_hdr(skb); struct amt_group_node *gnode; union amt_addr group, host; struct mld2_grec *grec; u16 nsrcs; int i; for (i = 0; i < ntohs(mld2r->mld2r_ngrec); i++) { len += sizeof(*grec); if (!ipv6_mc_may_pull(skb, len)) break; grec = (void *)(skb->data + len - sizeof(*grec)); nsrcs = ntohs(grec->grec_nsrcs); len += nsrcs * sizeof(struct in6_addr); if (!ipv6_mc_may_pull(skb, len)) break; memset(&group, 0, sizeof(union amt_addr)); group.ip6 = grec->grec_mca; memset(&host, 0, sizeof(union amt_addr)); host.ip6 = ip6h->saddr; gnode = amt_lookup_group(tunnel, &group, &host, true); if (!gnode) { gnode = amt_add_group(amt, tunnel, &group, &host, ETH_P_IPV6); if (IS_ERR(gnode)) continue; } amt_add_srcs(amt, tunnel, gnode, grec, true); switch (grec->grec_type) { case MLD2_MODE_IS_INCLUDE: amt_mcast_is_in_handler(amt, tunnel, gnode, grec, zero_grec, true); break; case MLD2_MODE_IS_EXCLUDE: amt_mcast_is_ex_handler(amt, tunnel, gnode, grec, zero_grec, true); break; case MLD2_CHANGE_TO_INCLUDE: amt_mcast_to_in_handler(amt, tunnel, gnode, grec, zero_grec, true); break; case MLD2_CHANGE_TO_EXCLUDE: amt_mcast_to_ex_handler(amt, tunnel, gnode, grec, zero_grec, true); break; case MLD2_ALLOW_NEW_SOURCES: amt_mcast_allow_handler(amt, tunnel, gnode, grec, zero_grec, true); break; case MLD2_BLOCK_OLD_SOURCES: amt_mcast_block_handler(amt, tunnel, gnode, grec, zero_grec, true); break; default: break; } amt_cleanup_srcs(amt, tunnel, gnode); } } /* caller held tunnel->lock */ static void amt_mld_report_handler(struct amt_dev *amt, struct sk_buff *skb, struct amt_tunnel_list *tunnel) { struct mld_msg *mld = (struct mld_msg *)icmp6_hdr(skb); switch (mld->mld_type) { case ICMPV6_MGM_REPORT: amt_mldv1_report_handler(amt, skb, tunnel); break; case ICMPV6_MLD2_REPORT: amt_mldv2_report_handler(amt, skb, tunnel); break; case ICMPV6_MGM_REDUCTION: amt_mldv1_leave_handler(amt, skb, tunnel); break; default: break; } } #endif static bool amt_advertisement_handler(struct amt_dev *amt, struct sk_buff *skb) { struct amt_header_advertisement *amta; int hdr_size; hdr_size = sizeof(*amta) + sizeof(struct udphdr); if (!pskb_may_pull(skb, hdr_size)) return true; amta = (struct amt_header_advertisement *)(udp_hdr(skb) + 1); if (!amta->ip4) return true; if (amta->reserved || amta->version) return true; if (ipv4_is_loopback(amta->ip4) || ipv4_is_multicast(amta->ip4) || ipv4_is_zeronet(amta->ip4)) return true; if (amt->status != AMT_STATUS_SENT_DISCOVERY || amt->nonce != amta->nonce) return true; amt->remote_ip = amta->ip4; netdev_dbg(amt->dev, "advertised remote ip = %pI4\n", &amt->remote_ip); mod_delayed_work(amt_wq, &amt->req_wq, 0); amt_update_gw_status(amt, AMT_STATUS_RECEIVED_ADVERTISEMENT, true); return false; } static bool amt_multicast_data_handler(struct amt_dev *amt, struct sk_buff *skb) { struct amt_header_mcast_data *amtmd; int hdr_size, len, err; struct ethhdr *eth; struct iphdr *iph; if (READ_ONCE(amt->status) != AMT_STATUS_SENT_UPDATE) return true; hdr_size = sizeof(*amtmd) + sizeof(struct udphdr); if (!pskb_may_pull(skb, hdr_size)) return true; amtmd = (struct amt_header_mcast_data *)(udp_hdr(skb) + 1); if (amtmd->reserved || amtmd->version) return true; if (iptunnel_pull_header(skb, hdr_size, htons(ETH_P_IP), false)) return true; skb_reset_network_header(skb); skb_push(skb, sizeof(*eth)); skb_reset_mac_header(skb); skb_pull(skb, sizeof(*eth)); eth = eth_hdr(skb); if (!pskb_may_pull(skb, sizeof(*iph))) return true; iph = ip_hdr(skb); if (iph->version == 4) { if (!ipv4_is_multicast(iph->daddr)) return true; skb->protocol = htons(ETH_P_IP); eth->h_proto = htons(ETH_P_IP); ip_eth_mc_map(iph->daddr, eth->h_dest); #if IS_ENABLED(CONFIG_IPV6) } else if (iph->version == 6) { struct ipv6hdr *ip6h; if (!pskb_may_pull(skb, sizeof(*ip6h))) return true; ip6h = ipv6_hdr(skb); if (!ipv6_addr_is_multicast(&ip6h->daddr)) return true; skb->protocol = htons(ETH_P_IPV6); eth->h_proto = htons(ETH_P_IPV6); ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest); #endif } else { return true; } skb->pkt_type = PACKET_MULTICAST; skb->ip_summed = CHECKSUM_NONE; len = skb->len; err = gro_cells_receive(&amt->gro_cells, skb); if (likely(err == NET_RX_SUCCESS)) dev_sw_netstats_rx_add(amt->dev, len); else amt->dev->stats.rx_dropped++; return false; } static bool amt_membership_query_handler(struct amt_dev *amt, struct sk_buff *skb) { struct amt_header_membership_query *amtmq; struct igmpv3_query *ihv3; struct ethhdr *eth, *oeth; struct iphdr *iph; int hdr_size, len; hdr_size = sizeof(*amtmq) + sizeof(struct udphdr); if (!pskb_may_pull(skb, hdr_size)) return true; amtmq = (struct amt_header_membership_query *)(udp_hdr(skb) + 1); if (amtmq->reserved || amtmq->version) return true; if (amtmq->nonce != amt->nonce) return true; hdr_size -= sizeof(*eth); if (iptunnel_pull_header(skb, hdr_size, htons(ETH_P_TEB), false)) return true; oeth = eth_hdr(skb); skb_reset_mac_header(skb); skb_pull(skb, sizeof(*eth)); skb_reset_network_header(skb); eth = eth_hdr(skb); if (!pskb_may_pull(skb, sizeof(*iph))) return true; iph = ip_hdr(skb); if (iph->version == 4) { if (READ_ONCE(amt->ready4)) return true; if (!pskb_may_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS + sizeof(*ihv3))) return true; if (!ipv4_is_multicast(iph->daddr)) return true; ihv3 = skb_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS); skb_reset_transport_header(skb); skb_push(skb, sizeof(*iph) + AMT_IPHDR_OPTS); WRITE_ONCE(amt->ready4, true); amt->mac = amtmq->response_mac; amt->req_cnt = 0; amt->qi = ihv3->qqic; skb->protocol = htons(ETH_P_IP); eth->h_proto = htons(ETH_P_IP); ip_eth_mc_map(iph->daddr, eth->h_dest); #if IS_ENABLED(CONFIG_IPV6) } else if (iph->version == 6) { struct mld2_query *mld2q; struct ipv6hdr *ip6h; if (READ_ONCE(amt->ready6)) return true; if (!pskb_may_pull(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS + sizeof(*mld2q))) return true; ip6h = ipv6_hdr(skb); if (!ipv6_addr_is_multicast(&ip6h->daddr)) return true; mld2q = skb_pull(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS); skb_reset_transport_header(skb); skb_push(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS); WRITE_ONCE(amt->ready6, true); amt->mac = amtmq->response_mac; amt->req_cnt = 0; amt->qi = mld2q->mld2q_qqic; skb->protocol = htons(ETH_P_IPV6); eth->h_proto = htons(ETH_P_IPV6); ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest); #endif } else { return true; } ether_addr_copy(eth->h_source, oeth->h_source); skb->pkt_type = PACKET_MULTICAST; skb->ip_summed = CHECKSUM_NONE; len = skb->len; local_bh_disable(); if (__netif_rx(skb) == NET_RX_SUCCESS) { amt_update_gw_status(amt, AMT_STATUS_RECEIVED_QUERY, true); dev_sw_netstats_rx_add(amt->dev, len); } else { amt->dev->stats.rx_dropped++; } local_bh_enable(); return false; } static bool amt_update_handler(struct amt_dev *amt, struct sk_buff *skb) { struct amt_header_membership_update *amtmu; struct amt_tunnel_list *tunnel; struct ethhdr *eth; struct iphdr *iph; int len, hdr_size; iph = ip_hdr(skb); hdr_size = sizeof(*amtmu) + sizeof(struct udphdr); if (!pskb_may_pull(skb, hdr_size)) return true; amtmu = (struct amt_header_membership_update *)(udp_hdr(skb) + 1); if (amtmu->reserved || amtmu->version) return true; if (iptunnel_pull_header(skb, hdr_size, skb->protocol, false)) return true; skb_reset_network_header(skb); list_for_each_entry_rcu(tunnel, &amt->tunnel_list, list) { if (tunnel->ip4 == iph->saddr) { if ((amtmu->nonce == tunnel->nonce && amtmu->response_mac == tunnel->mac)) { mod_delayed_work(amt_wq, &tunnel->gc_wq, msecs_to_jiffies(amt_gmi(amt)) * 3); goto report; } else { netdev_dbg(amt->dev, "Invalid MAC\n"); return true; } } } return true; report: if (!pskb_may_pull(skb, sizeof(*iph))) return true; iph = ip_hdr(skb); if (iph->version == 4) { if (ip_mc_check_igmp(skb)) { netdev_dbg(amt->dev, "Invalid IGMP\n"); return true; } spin_lock_bh(&tunnel->lock); amt_igmp_report_handler(amt, skb, tunnel); spin_unlock_bh(&tunnel->lock); skb_push(skb, sizeof(struct ethhdr)); skb_reset_mac_header(skb); eth = eth_hdr(skb); skb->protocol = htons(ETH_P_IP); eth->h_proto = htons(ETH_P_IP); ip_eth_mc_map(iph->daddr, eth->h_dest); #if IS_ENABLED(CONFIG_IPV6) } else if (iph->version == 6) { struct ipv6hdr *ip6h = ipv6_hdr(skb); if (ipv6_mc_check_mld(skb)) { netdev_dbg(amt->dev, "Invalid MLD\n"); return true; } spin_lock_bh(&tunnel->lock); amt_mld_report_handler(amt, skb, tunnel); spin_unlock_bh(&tunnel->lock); skb_push(skb, sizeof(struct ethhdr)); skb_reset_mac_header(skb); eth = eth_hdr(skb); skb->protocol = htons(ETH_P_IPV6); eth->h_proto = htons(ETH_P_IPV6); ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest); #endif } else { netdev_dbg(amt->dev, "Unsupported Protocol\n"); return true; } skb_pull(skb, sizeof(struct ethhdr)); skb->pkt_type = PACKET_MULTICAST; skb->ip_summed = CHECKSUM_NONE; len = skb->len; if (__netif_rx(skb) == NET_RX_SUCCESS) { amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_UPDATE, true); dev_sw_netstats_rx_add(amt->dev, len); } else { amt->dev->stats.rx_dropped++; } return false; } static void amt_send_advertisement(struct amt_dev *amt, __be32 nonce, __be32 daddr, __be16 dport) { struct amt_header_advertisement *amta; int hlen, tlen, offset; struct socket *sock; struct udphdr *udph; struct sk_buff *skb; struct iphdr *iph; struct rtable *rt; struct flowi4 fl4; u32 len; int err; rcu_read_lock(); sock = rcu_dereference(amt->sock); if (!sock) goto out; if (!netif_running(amt->stream_dev) || !netif_running(amt->dev)) goto out; rt = ip_route_output_ports(amt->net, &fl4, sock->sk, daddr, amt->local_ip, dport, amt->relay_port, IPPROTO_UDP, 0, amt->stream_dev->ifindex); if (IS_ERR(rt)) { amt->dev->stats.tx_errors++; goto out; } hlen = LL_RESERVED_SPACE(amt->dev); tlen = amt->dev->needed_tailroom; len = hlen + tlen + sizeof(*iph) + sizeof(*udph) + sizeof(*amta); skb = netdev_alloc_skb_ip_align(amt->dev, len); if (!skb) { ip_rt_put(rt); amt->dev->stats.tx_errors++; goto out; } skb->priority = TC_PRIO_CONTROL; skb_dst_set(skb, &rt->dst); len = sizeof(*iph) + sizeof(*udph) + sizeof(*amta); skb_reset_network_header(skb); skb_put(skb, len); amta = skb_pull(skb, sizeof(*iph) + sizeof(*udph)); amta->version = 0; amta->type = AMT_MSG_ADVERTISEMENT; amta->reserved = 0; amta->nonce = nonce; amta->ip4 = amt->local_ip; skb_push(skb, sizeof(*udph)); skb_reset_transport_header(skb); udph = udp_hdr(skb); udph->source = amt->relay_port; udph->dest = dport; udph->len = htons(sizeof(*amta) + sizeof(*udph)); udph->check = 0; offset = skb_transport_offset(skb); skb->csum = skb_checksum(skb, offset, skb->len - offset, 0); udph->check = csum_tcpudp_magic(amt->local_ip, daddr, sizeof(*udph) + sizeof(*amta), IPPROTO_UDP, skb->csum); skb_push(skb, sizeof(*iph)); iph = ip_hdr(skb); iph->version = 4; iph->ihl = (sizeof(struct iphdr)) >> 2; iph->tos = AMT_TOS; iph->frag_off = 0; iph->ttl = ip4_dst_hoplimit(&rt->dst); iph->daddr = daddr; iph->saddr = amt->local_ip; iph->protocol = IPPROTO_UDP; iph->tot_len = htons(len); skb->ip_summed = CHECKSUM_NONE; ip_select_ident(amt->net, skb, NULL); ip_send_check(iph); err = ip_local_out(amt->net, sock->sk, skb); if (unlikely(net_xmit_eval(err))) amt->dev->stats.tx_errors++; out: rcu_read_unlock(); } static bool amt_discovery_handler(struct amt_dev *amt, struct sk_buff *skb) { struct amt_header_discovery *amtd; struct udphdr *udph; struct iphdr *iph; if (!pskb_may_pull(skb, sizeof(*udph) + sizeof(*amtd))) return true; iph = ip_hdr(skb); udph = udp_hdr(skb); amtd = (struct amt_header_discovery *)(udp_hdr(skb) + 1); if (amtd->reserved || amtd->version) return true; amt_send_advertisement(amt, amtd->nonce, iph->saddr, udph->source); return false; } static bool amt_request_handler(struct amt_dev *amt, struct sk_buff *skb) { struct amt_header_request *amtrh; struct amt_tunnel_list *tunnel; unsigned long long key; struct udphdr *udph; struct iphdr *iph; u64 mac; int i; if (!pskb_may_pull(skb, sizeof(*udph) + sizeof(*amtrh))) return true; iph = ip_hdr(skb); udph = udp_hdr(skb); amtrh = (struct amt_header_request *)(udp_hdr(skb) + 1); if (amtrh->reserved1 || amtrh->reserved2 || amtrh->version) return true; list_for_each_entry_rcu(tunnel, &amt->tunnel_list, list) if (tunnel->ip4 == iph->saddr) goto send; spin_lock_bh(&amt->lock); if (amt->nr_tunnels >= amt->max_tunnels) { spin_unlock_bh(&amt->lock); icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); return true; } tunnel = kzalloc(sizeof(*tunnel) + (sizeof(struct hlist_head) * amt->hash_buckets), GFP_ATOMIC); if (!tunnel) { spin_unlock_bh(&amt->lock); return true; } tunnel->source_port = udph->source; tunnel->ip4 = iph->saddr; memcpy(&key, &tunnel->key, sizeof(unsigned long long)); tunnel->amt = amt; spin_lock_init(&tunnel->lock); for (i = 0; i < amt->hash_buckets; i++) INIT_HLIST_HEAD(&tunnel->groups[i]); INIT_DELAYED_WORK(&tunnel->gc_wq, amt_tunnel_expire); list_add_tail_rcu(&tunnel->list, &amt->tunnel_list); tunnel->key = amt->key; __amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_REQUEST, true); amt->nr_tunnels++; mod_delayed_work(amt_wq, &tunnel->gc_wq, msecs_to_jiffies(amt_gmi(amt))); spin_unlock_bh(&amt->lock); send: tunnel->nonce = amtrh->nonce; mac = siphash_3u32((__force u32)tunnel->ip4, (__force u32)tunnel->source_port, (__force u32)tunnel->nonce, &tunnel->key); tunnel->mac = mac >> 16; if (!netif_running(amt->dev) || !netif_running(amt->stream_dev)) return true; if (!amtrh->p) amt_send_igmp_gq(amt, tunnel); else amt_send_mld_gq(amt, tunnel); return false; } static void amt_gw_rcv(struct amt_dev *amt, struct sk_buff *skb) { int type = amt_parse_type(skb); int err = 1; if (type == -1) goto drop; if (amt->mode == AMT_MODE_GATEWAY) { switch (type) { case AMT_MSG_ADVERTISEMENT: err = amt_advertisement_handler(amt, skb); break; case AMT_MSG_MEMBERSHIP_QUERY: err = amt_membership_query_handler(amt, skb); if (!err) return; break; default: netdev_dbg(amt->dev, "Invalid type of Gateway\n"); break; } } drop: if (err) { amt->dev->stats.rx_dropped++; kfree_skb(skb); } else { consume_skb(skb); } } static int amt_rcv(struct sock *sk, struct sk_buff *skb) { struct amt_dev *amt; struct iphdr *iph; int type; bool err; rcu_read_lock_bh(); amt = rcu_dereference_sk_user_data(sk); if (!amt) { err = true; kfree_skb(skb); goto out; } skb->dev = amt->dev; iph = ip_hdr(skb); type = amt_parse_type(skb); if (type == -1) { err = true; goto drop; } if (amt->mode == AMT_MODE_GATEWAY) { switch (type) { case AMT_MSG_ADVERTISEMENT: if (iph->saddr != amt->discovery_ip) { netdev_dbg(amt->dev, "Invalid Relay IP\n"); err = true; goto drop; } if (amt_queue_event(amt, AMT_EVENT_RECEIVE, skb)) { netdev_dbg(amt->dev, "AMT Event queue full\n"); err = true; goto drop; } goto out; case AMT_MSG_MULTICAST_DATA: if (iph->saddr != amt->remote_ip) { netdev_dbg(amt->dev, "Invalid Relay IP\n"); err = true; goto drop; } err = amt_multicast_data_handler(amt, skb); if (err) goto drop; else goto out; case AMT_MSG_MEMBERSHIP_QUERY: if (iph->saddr != amt->remote_ip) { netdev_dbg(amt->dev, "Invalid Relay IP\n"); err = true; goto drop; } if (amt_queue_event(amt, AMT_EVENT_RECEIVE, skb)) { netdev_dbg(amt->dev, "AMT Event queue full\n"); err = true; goto drop; } goto out; default: err = true; netdev_dbg(amt->dev, "Invalid type of Gateway\n"); break; } } else { switch (type) { case AMT_MSG_DISCOVERY: err = amt_discovery_handler(amt, skb); break; case AMT_MSG_REQUEST: err = amt_request_handler(amt, skb); break; case AMT_MSG_MEMBERSHIP_UPDATE: err = amt_update_handler(amt, skb); if (err) goto drop; else goto out; default: err = true; netdev_dbg(amt->dev, "Invalid type of relay\n"); break; } } drop: if (err) { amt->dev->stats.rx_dropped++; kfree_skb(skb); } else { consume_skb(skb); } out: rcu_read_unlock_bh(); return 0; } static void amt_event_work(struct work_struct *work) { struct amt_dev *amt = container_of(work, struct amt_dev, event_wq); struct sk_buff *skb; u8 event; int i; for (i = 0; i < AMT_MAX_EVENTS; i++) { spin_lock_bh(&amt->lock); if (amt->nr_events == 0) { spin_unlock_bh(&amt->lock); return; } event = amt->events[amt->event_idx].event; skb = amt->events[amt->event_idx].skb; amt->events[amt->event_idx].event = AMT_EVENT_NONE; amt->events[amt->event_idx].skb = NULL; amt->nr_events--; amt->event_idx++; amt->event_idx %= AMT_MAX_EVENTS; spin_unlock_bh(&amt->lock); switch (event) { case AMT_EVENT_RECEIVE: amt_gw_rcv(amt, skb); break; case AMT_EVENT_SEND_DISCOVERY: amt_event_send_discovery(amt); break; case AMT_EVENT_SEND_REQUEST: amt_event_send_request(amt); break; default: kfree_skb(skb); break; } } } static int amt_err_lookup(struct sock *sk, struct sk_buff *skb) { struct amt_dev *amt; int type; rcu_read_lock_bh(); amt = rcu_dereference_sk_user_data(sk); if (!amt) goto out; if (amt->mode != AMT_MODE_GATEWAY) goto drop; type = amt_parse_type(skb); if (type == -1) goto drop; netdev_dbg(amt->dev, "Received IGMP Unreachable of %s\n", type_str[type]); switch (type) { case AMT_MSG_DISCOVERY: break; case AMT_MSG_REQUEST: case AMT_MSG_MEMBERSHIP_UPDATE: if (READ_ONCE(amt->status) >= AMT_STATUS_RECEIVED_ADVERTISEMENT) mod_delayed_work(amt_wq, &amt->req_wq, 0); break; default: goto drop; } out: rcu_read_unlock_bh(); return 0; drop: rcu_read_unlock_bh(); amt->dev->stats.rx_dropped++; return 0; } static struct socket *amt_create_sock(struct net *net, __be16 port) { struct udp_port_cfg udp_conf; struct socket *sock; int err; memset(&udp_conf, 0, sizeof(udp_conf)); udp_conf.family = AF_INET; udp_conf.local_ip.s_addr = htonl(INADDR_ANY); udp_conf.local_udp_port = port; err = udp_sock_create(net, &udp_conf, &sock); if (err < 0) return ERR_PTR(err); return sock; } static int amt_socket_create(struct amt_dev *amt) { struct udp_tunnel_sock_cfg tunnel_cfg; struct socket *sock; sock = amt_create_sock(amt->net, amt->relay_port); if (IS_ERR(sock)) return PTR_ERR(sock); /* Mark socket as an encapsulation socket */ memset(&tunnel_cfg, 0, sizeof(tunnel_cfg)); tunnel_cfg.sk_user_data = amt; tunnel_cfg.encap_type = 1; tunnel_cfg.encap_rcv = amt_rcv; tunnel_cfg.encap_err_lookup = amt_err_lookup; tunnel_cfg.encap_destroy = NULL; setup_udp_tunnel_sock(amt->net, sock, &tunnel_cfg); rcu_assign_pointer(amt->sock, sock); return 0; } static int amt_dev_open(struct net_device *dev) { struct amt_dev *amt = netdev_priv(dev); int err; amt->ready4 = false; amt->ready6 = false; amt->event_idx = 0; amt->nr_events = 0; err = amt_socket_create(amt); if (err) return err; amt->req_cnt = 0; amt->remote_ip = 0; amt->nonce = 0; get_random_bytes(&amt->key, sizeof(siphash_key_t)); amt->status = AMT_STATUS_INIT; if (amt->mode == AMT_MODE_GATEWAY) { mod_delayed_work(amt_wq, &amt->discovery_wq, 0); mod_delayed_work(amt_wq, &amt->req_wq, 0); } else if (amt->mode == AMT_MODE_RELAY) { mod_delayed_work(amt_wq, &amt->secret_wq, msecs_to_jiffies(AMT_SECRET_TIMEOUT)); } return err; } static int amt_dev_stop(struct net_device *dev) { struct amt_dev *amt = netdev_priv(dev); struct amt_tunnel_list *tunnel, *tmp; struct socket *sock; struct sk_buff *skb; int i; cancel_delayed_work_sync(&amt->req_wq); cancel_delayed_work_sync(&amt->discovery_wq); cancel_delayed_work_sync(&amt->secret_wq); /* shutdown */ sock = rtnl_dereference(amt->sock); RCU_INIT_POINTER(amt->sock, NULL); synchronize_net(); if (sock) udp_tunnel_sock_release(sock); cancel_work_sync(&amt->event_wq); for (i = 0; i < AMT_MAX_EVENTS; i++) { skb = amt->events[i].skb; kfree_skb(skb); amt->events[i].event = AMT_EVENT_NONE; amt->events[i].skb = NULL; } amt->ready4 = false; amt->ready6 = false; amt->req_cnt = 0; amt->remote_ip = 0; list_for_each_entry_safe(tunnel, tmp, &amt->tunnel_list, list) { list_del_rcu(&tunnel->list); amt->nr_tunnels--; cancel_delayed_work_sync(&tunnel->gc_wq); amt_clear_groups(tunnel); kfree_rcu(tunnel, rcu); } return 0; } static const struct device_type amt_type = { .name = "amt", }; static int amt_dev_init(struct net_device *dev) { struct amt_dev *amt = netdev_priv(dev); int err; amt->dev = dev; err = gro_cells_init(&amt->gro_cells, dev); if (err) return err; return 0; } static void amt_dev_uninit(struct net_device *dev) { struct amt_dev *amt = netdev_priv(dev); gro_cells_destroy(&amt->gro_cells); } static const struct net_device_ops amt_netdev_ops = { .ndo_init = amt_dev_init, .ndo_uninit = amt_dev_uninit, .ndo_open = amt_dev_open, .ndo_stop = amt_dev_stop, .ndo_start_xmit = amt_dev_xmit, }; static void amt_link_setup(struct net_device *dev) { dev->netdev_ops = &amt_netdev_ops; dev->needs_free_netdev = true; SET_NETDEV_DEVTYPE(dev, &amt_type); dev->min_mtu = ETH_MIN_MTU; dev->max_mtu = ETH_MAX_MTU; dev->type = ARPHRD_NONE; dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; dev->hard_header_len = 0; dev->addr_len = 0; dev->priv_flags |= IFF_NO_QUEUE; dev->lltx = true; dev->netns_local = true; dev->features |= NETIF_F_GSO_SOFTWARE; dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM; dev->hw_features |= NETIF_F_FRAGLIST | NETIF_F_RXCSUM; dev->hw_features |= NETIF_F_GSO_SOFTWARE; dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS; eth_hw_addr_random(dev); eth_zero_addr(dev->broadcast); ether_setup(dev); } static const struct nla_policy amt_policy[IFLA_AMT_MAX + 1] = { [IFLA_AMT_MODE] = { .type = NLA_U32 }, [IFLA_AMT_RELAY_PORT] = { .type = NLA_U16 }, [IFLA_AMT_GATEWAY_PORT] = { .type = NLA_U16 }, [IFLA_AMT_LINK] = { .type = NLA_U32 }, [IFLA_AMT_LOCAL_IP] = { .len = sizeof_field(struct iphdr, daddr) }, [IFLA_AMT_REMOTE_IP] = { .len = sizeof_field(struct iphdr, daddr) }, [IFLA_AMT_DISCOVERY_IP] = { .len = sizeof_field(struct iphdr, daddr) }, [IFLA_AMT_MAX_TUNNELS] = { .type = NLA_U32 }, }; static int amt_validate(struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { if (!data) return -EINVAL; if (!data[IFLA_AMT_LINK]) { NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_LINK], "Link attribute is required"); return -EINVAL; } if (!data[IFLA_AMT_MODE]) { NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_MODE], "Mode attribute is required"); return -EINVAL; } if (nla_get_u32(data[IFLA_AMT_MODE]) > AMT_MODE_MAX) { NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_MODE], "Mode attribute is not valid"); return -EINVAL; } if (!data[IFLA_AMT_LOCAL_IP]) { NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_DISCOVERY_IP], "Local attribute is required"); return -EINVAL; } if (!data[IFLA_AMT_DISCOVERY_IP] && nla_get_u32(data[IFLA_AMT_MODE]) == AMT_MODE_GATEWAY) { NL_SET_ERR_MSG_ATTR(extack, data[IFLA_AMT_LOCAL_IP], "Discovery attribute is required"); return -EINVAL; } return 0; } static int amt_newlink(struct net *net, struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { struct amt_dev *amt = netdev_priv(dev); int err = -EINVAL; amt->net = net; amt->mode = nla_get_u32(data[IFLA_AMT_MODE]); if (data[IFLA_AMT_MAX_TUNNELS] && nla_get_u32(data[IFLA_AMT_MAX_TUNNELS])) amt->max_tunnels = nla_get_u32(data[IFLA_AMT_MAX_TUNNELS]); else amt->max_tunnels = AMT_MAX_TUNNELS; spin_lock_init(&amt->lock); amt->max_groups = AMT_MAX_GROUP; amt->max_sources = AMT_MAX_SOURCE; amt->hash_buckets = AMT_HSIZE; amt->nr_tunnels = 0; get_random_bytes(&amt->hash_seed, sizeof(amt->hash_seed)); amt->stream_dev = dev_get_by_index(net, nla_get_u32(data[IFLA_AMT_LINK])); if (!amt->stream_dev) { NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_LINK], "Can't find stream device"); return -ENODEV; } if (amt->stream_dev->type != ARPHRD_ETHER) { NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_LINK], "Invalid stream device type"); goto err; } amt->local_ip = nla_get_in_addr(data[IFLA_AMT_LOCAL_IP]); if (ipv4_is_loopback(amt->local_ip) || ipv4_is_zeronet(amt->local_ip) || ipv4_is_multicast(amt->local_ip)) { NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_LOCAL_IP], "Invalid Local address"); goto err; } if (data[IFLA_AMT_RELAY_PORT]) amt->relay_port = nla_get_be16(data[IFLA_AMT_RELAY_PORT]); else amt->relay_port = htons(IANA_AMT_UDP_PORT); if (data[IFLA_AMT_GATEWAY_PORT]) amt->gw_port = nla_get_be16(data[IFLA_AMT_GATEWAY_PORT]); else amt->gw_port = htons(IANA_AMT_UDP_PORT); if (!amt->relay_port) { NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_DISCOVERY_IP], "relay port must not be 0"); goto err; } if (amt->mode == AMT_MODE_RELAY) { amt->qrv = READ_ONCE(amt->net->ipv4.sysctl_igmp_qrv); amt->qri = 10; dev->needed_headroom = amt->stream_dev->needed_headroom + AMT_RELAY_HLEN; dev->mtu = amt->stream_dev->mtu - AMT_RELAY_HLEN; dev->max_mtu = dev->mtu; dev->min_mtu = ETH_MIN_MTU + AMT_RELAY_HLEN; } else { if (!data[IFLA_AMT_DISCOVERY_IP]) { NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_DISCOVERY_IP], "discovery must be set in gateway mode"); goto err; } if (!amt->gw_port) { NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_DISCOVERY_IP], "gateway port must not be 0"); goto err; } amt->remote_ip = 0; amt->discovery_ip = nla_get_in_addr(data[IFLA_AMT_DISCOVERY_IP]); if (ipv4_is_loopback(amt->discovery_ip) || ipv4_is_zeronet(amt->discovery_ip) || ipv4_is_multicast(amt->discovery_ip)) { NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_DISCOVERY_IP], "discovery must be unicast"); goto err; } dev->needed_headroom = amt->stream_dev->needed_headroom + AMT_GW_HLEN; dev->mtu = amt->stream_dev->mtu - AMT_GW_HLEN; dev->max_mtu = dev->mtu; dev->min_mtu = ETH_MIN_MTU + AMT_GW_HLEN; } amt->qi = AMT_INIT_QUERY_INTERVAL; err = register_netdevice(dev); if (err < 0) { netdev_dbg(dev, "failed to register new netdev %d\n", err); goto err; } err = netdev_upper_dev_link(amt->stream_dev, dev, extack); if (err < 0) { unregister_netdevice(dev); goto err; } INIT_DELAYED_WORK(&amt->discovery_wq, amt_discovery_work); INIT_DELAYED_WORK(&amt->req_wq, amt_req_work); INIT_DELAYED_WORK(&amt->secret_wq, amt_secret_work); INIT_WORK(&amt->event_wq, amt_event_work); INIT_LIST_HEAD(&amt->tunnel_list); return 0; err: dev_put(amt->stream_dev); return err; } static void amt_dellink(struct net_device *dev, struct list_head *head) { struct amt_dev *amt = netdev_priv(dev); unregister_netdevice_queue(dev, head); netdev_upper_dev_unlink(amt->stream_dev, dev); dev_put(amt->stream_dev); } static size_t amt_get_size(const struct net_device *dev) { return nla_total_size(sizeof(__u32)) + /* IFLA_AMT_MODE */ nla_total_size(sizeof(__u16)) + /* IFLA_AMT_RELAY_PORT */ nla_total_size(sizeof(__u16)) + /* IFLA_AMT_GATEWAY_PORT */ nla_total_size(sizeof(__u32)) + /* IFLA_AMT_LINK */ nla_total_size(sizeof(__u32)) + /* IFLA_MAX_TUNNELS */ nla_total_size(sizeof(struct iphdr)) + /* IFLA_AMT_DISCOVERY_IP */ nla_total_size(sizeof(struct iphdr)) + /* IFLA_AMT_REMOTE_IP */ nla_total_size(sizeof(struct iphdr)); /* IFLA_AMT_LOCAL_IP */ } static int amt_fill_info(struct sk_buff *skb, const struct net_device *dev) { struct amt_dev *amt = netdev_priv(dev); if (nla_put_u32(skb, IFLA_AMT_MODE, amt->mode)) goto nla_put_failure; if (nla_put_be16(skb, IFLA_AMT_RELAY_PORT, amt->relay_port)) goto nla_put_failure; if (nla_put_be16(skb, IFLA_AMT_GATEWAY_PORT, amt->gw_port)) goto nla_put_failure; if (nla_put_u32(skb, IFLA_AMT_LINK, amt->stream_dev->ifindex)) goto nla_put_failure; if (nla_put_in_addr(skb, IFLA_AMT_LOCAL_IP, amt->local_ip)) goto nla_put_failure; if (nla_put_in_addr(skb, IFLA_AMT_DISCOVERY_IP, amt->discovery_ip)) goto nla_put_failure; if (amt->remote_ip) if (nla_put_in_addr(skb, IFLA_AMT_REMOTE_IP, amt->remote_ip)) goto nla_put_failure; if (nla_put_u32(skb, IFLA_AMT_MAX_TUNNELS, amt->max_tunnels)) goto nla_put_failure; return 0; nla_put_failure: return -EMSGSIZE; } static struct rtnl_link_ops amt_link_ops __read_mostly = { .kind = "amt", .maxtype = IFLA_AMT_MAX, .policy = amt_policy, .priv_size = sizeof(struct amt_dev), .setup = amt_link_setup, .validate = amt_validate, .newlink = amt_newlink, .dellink = amt_dellink, .get_size = amt_get_size, .fill_info = amt_fill_info, }; static struct net_device *amt_lookup_upper_dev(struct net_device *dev) { struct net_device *upper_dev; struct amt_dev *amt; for_each_netdev(dev_net(dev), upper_dev) { if (netif_is_amt(upper_dev)) { amt = netdev_priv(upper_dev); if (amt->stream_dev == dev) return upper_dev; } } return NULL; } static int amt_device_event(struct notifier_block *unused, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct net_device *upper_dev; struct amt_dev *amt; LIST_HEAD(list); int new_mtu; upper_dev = amt_lookup_upper_dev(dev); if (!upper_dev) return NOTIFY_DONE; amt = netdev_priv(upper_dev); switch (event) { case NETDEV_UNREGISTER: amt_dellink(amt->dev, &list); unregister_netdevice_many(&list); break; case NETDEV_CHANGEMTU: if (amt->mode == AMT_MODE_RELAY) new_mtu = dev->mtu - AMT_RELAY_HLEN; else new_mtu = dev->mtu - AMT_GW_HLEN; dev_set_mtu(amt->dev, new_mtu); break; } return NOTIFY_DONE; } static struct notifier_block amt_notifier_block __read_mostly = { .notifier_call = amt_device_event, }; static int __init amt_init(void) { int err; err = register_netdevice_notifier(&amt_notifier_block); if (err < 0) goto err; err = rtnl_link_register(&amt_link_ops); if (err < 0) goto unregister_notifier; amt_wq = alloc_workqueue("amt", WQ_UNBOUND, 0); if (!amt_wq) { err = -ENOMEM; goto rtnl_unregister; } spin_lock_init(&source_gc_lock); spin_lock_bh(&source_gc_lock); INIT_DELAYED_WORK(&source_gc_wq, amt_source_gc_work); mod_delayed_work(amt_wq, &source_gc_wq, msecs_to_jiffies(AMT_GC_INTERVAL)); spin_unlock_bh(&source_gc_lock); return 0; rtnl_unregister: rtnl_link_unregister(&amt_link_ops); unregister_notifier: unregister_netdevice_notifier(&amt_notifier_block); err: pr_err("error loading AMT module loaded\n"); return err; } late_initcall(amt_init); static void __exit amt_fini(void) { rtnl_link_unregister(&amt_link_ops); unregister_netdevice_notifier(&amt_notifier_block); cancel_delayed_work_sync(&source_gc_wq); __amt_source_gc_work(); destroy_workqueue(amt_wq); } module_exit(amt_fini); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Driver for Automatic Multicast Tunneling (AMT)"); MODULE_AUTHOR("Taehee Yoo "); MODULE_ALIAS_RTNL_LINK("amt");