diff options
| -rw-r--r-- | drivers/net/amt.c | 1242 | ||||
| -rw-r--r-- | include/net/amt.h | 47 |
2 files changed, 1288 insertions, 1 deletions
diff --git a/drivers/net/amt.c b/drivers/net/amt.c index addab3b1de0a..b4aff24ef271 100644 --- a/drivers/net/amt.c +++ b/drivers/net/amt.c @@ -32,6 +32,1218 @@ static struct workqueue_struct *amt_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[] = { + "AMT_MSG_DISCOVERY", + "AMT_MSG_ADVERTISEMENT", + "AMT_MSG_REQUEST", + "AMT_MSG_MEMBERSHIP_QUERY", + "AMT_MSG_MEMBERSHIP_UPDATE", + "AMT_MSG_MULTICAST_DATA", + "AMT_MSG_TEARDOWM", +}; + +static struct amt_skb_cb *amt_skb_cb(struct sk_buff *skb) +{ + BUILD_BUG_ON(sizeof(struct amt_skb_cb) + sizeof(struct qdisc_skb_cb) > + sizeof_field(struct sk_buff, cb)); + + return (struct amt_skb_cb *)((void *)skb->cb + + sizeof(struct qdisc_skb_cb)); +} + +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 = 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]); + 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_gw_status(struct amt_dev *amt, enum amt_status status, + bool validate) +{ + spin_lock_bh(&amt->lock); + __amt_update_gw_status(amt, status, validate); + spin_unlock_bh(&amt->lock); +} + +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++; + + spin_lock_bh(&amt->lock); + __amt_update_gw_status(amt, AMT_STATUS_SENT_DISCOVERY, true); + spin_unlock_bh(&amt->lock); +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); +} + +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_discovery_work(struct work_struct *work) +{ + struct amt_dev *amt = container_of(to_delayed_work(work), + struct amt_dev, + discovery_wq); + + spin_lock_bh(&amt->lock); + if (amt->status > AMT_STATUS_SENT_DISCOVERY) + goto out; + get_random_bytes(&amt->nonce, sizeof(__be32)); + spin_unlock_bh(&amt->lock); + + amt_send_discovery(amt); + spin_lock_bh(&amt->lock); +out: + mod_delayed_work(amt_wq, &amt->discovery_wq, + msecs_to_jiffies(AMT_DISCOVERY_TIMEOUT)); + spin_unlock_bh(&amt->lock); +} + +static void amt_req_work(struct work_struct *work) +{ + struct amt_dev *amt = container_of(to_delayed_work(work), + struct amt_dev, + req_wq); + u32 exp; + + spin_lock_bh(&amt->lock); + 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; + amt->ready4 = false; + amt->ready6 = false; + amt->remote_ip = 0; + __amt_update_gw_status(amt, AMT_STATUS_INIT, false); + amt->req_cnt = 0; + } + spin_unlock_bh(&amt->lock); + + amt_send_request(amt, false); + amt_send_request(amt, true); + amt_update_gw_status(amt, AMT_STATUS_SENT_REQUEST, true); + spin_lock_bh(&amt->lock); +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)); + spin_unlock_bh(&amt->lock); +} + +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 -1; + } + + 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; + bool report = false; + struct igmphdr *ih; + bool query = false; + struct iphdr *iph; + bool data = false; + bool v6 = false; + + 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; + } 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 && !amt->ready4) || (v6 && !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) + 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_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--; + rcu_read_unlock(); + spin_unlock_bh(&amt->lock); + kfree_rcu(tunnel, rcu); +} + +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 amt_header); + + 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; + + 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; + + amtmd = (struct amt_header_mcast_data *)(udp_hdr(skb) + 1); + if (amtmd->reserved || amtmd->version) + return true; + + hdr_size = sizeof(*amtmd) + sizeof(struct udphdr); + 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); + 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); + } 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 amt_header); + + 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; + + hdr_size = sizeof(*amtmq) + sizeof(struct udphdr) - 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); + iph = ip_hdr(skb); + if (iph->version == 4) { + if (!ipv4_is_multicast(iph->daddr)) + return true; + if (!pskb_may_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS + + sizeof(*ihv3))) + return true; + + ihv3 = skb_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS); + skb_reset_transport_header(skb); + skb_push(skb, sizeof(*iph) + AMT_IPHDR_OPTS); + spin_lock_bh(&amt->lock); + amt->ready4 = true; + amt->mac = amtmq->response_mac; + amt->req_cnt = 0; + amt->qi = ihv3->qqic; + spin_unlock_bh(&amt->lock); + skb->protocol = htons(ETH_P_IP); + eth->h_proto = htons(ETH_P_IP); + ip_eth_mc_map(iph->daddr, eth->h_dest); + } 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; + 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++; + } + + 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 udphdr *udph; + struct ethhdr *eth; + struct iphdr *iph; + int len; + + iph = ip_hdr(skb); + udph = udp_hdr(skb); + + if (__iptunnel_pull_header(skb, sizeof(*udph), skb->protocol, + false, false)) + return true; + + amtmu = (struct amt_header_membership_update *)skb->data; + if (amtmu->reserved || amtmu->version) + return true; + + skb_pull(skb, sizeof(*amtmu)); + 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 false; + +report: + iph = ip_hdr(skb); + if (iph->version == 4) { + if (ip_mc_check_igmp(skb)) { + netdev_dbg(amt->dev, "Invalid IGMP\n"); + return true; + } + + 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); + } 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; + + if (amt->nr_tunnels >= amt->max_tunnels) { + 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) + 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); + + spin_lock_bh(&amt->lock); + 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); + + return false; +} + +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; + 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_advertisement_handler(amt, skb)) + amt->dev->stats.rx_dropped++; + 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; + } + err = amt_membership_query_handler(amt, skb); + if (err) + goto drop; + else + 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 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 drop; + + 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 (amt->status >= AMT_STATUS_RECEIVED_ADVERTISEMENT) + mod_delayed_work(amt_wq, &amt->req_wq, 0); + break; + default: + goto drop; + } + 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; @@ -64,6 +1276,8 @@ static int amt_socket_create(struct amt_dev *amt) 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); @@ -88,14 +1302,26 @@ static int amt_dev_open(struct net_device *dev) 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; + 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); @@ -108,6 +1334,13 @@ static int amt_dev_stop(struct net_device *dev) 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); + kfree_rcu(tunnel, rcu); + } + return 0; } @@ -147,6 +1380,7 @@ static const struct net_device_ops amt_netdev_ops = { .ndo_uninit = amt_dev_uninit, .ndo_open = amt_dev_open, .ndo_stop = amt_dev_stop, + .ndo_start_xmit = amt_dev_xmit, .ndo_get_stats64 = dev_get_tstats64, }; @@ -234,7 +1468,8 @@ static int amt_newlink(struct net *net, struct net_device *dev, amt->net = net; amt->mode = nla_get_u32(data[IFLA_AMT_MODE]); - if (data[IFLA_AMT_MAX_TUNNELS]) + 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; @@ -332,6 +1567,11 @@ static int amt_newlink(struct net *net, struct net_device *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_LIST_HEAD(&amt->tunnel_list); + return 0; err: dev_put(amt->stream_dev); diff --git a/include/net/amt.h b/include/net/amt.h index ce24ff823555..31b0cf17044b 100644 --- a/include/net/amt.h +++ b/include/net/amt.h @@ -38,6 +38,18 @@ enum amt_status { #define AMT_STATUS_MAX (__AMT_STATUS_MAX - 1) +struct amt_header { +#if defined(__LITTLE_ENDIAN_BITFIELD) + u8 type:4, + version:4; +#elif defined(__BIG_ENDIAN_BITFIELD) + u8 version:4, + type:4; +#else +#error "Please fix <asm/byteorder.h>" +#endif +} __packed; + struct amt_header_discovery { #if defined(__LITTLE_ENDIAN_BITFIELD) u32 type:4, @@ -156,6 +168,29 @@ struct amt_relay_headers { }; } __packed; +struct amt_skb_cb { + struct amt_tunnel_list *tunnel; +}; + +struct amt_tunnel_list { + struct list_head list; + /* Protect All resources under an amt_tunne_list */ + spinlock_t lock; + struct amt_dev *amt; + u32 nr_groups; + u32 nr_sources; + enum amt_status status; + struct delayed_work gc_wq; + __be16 source_port; + __be32 ip4; + __be32 nonce; + siphash_key_t key; + u64 mac:48, + reserved:16; + struct rcu_head rcu; + struct hlist_head groups[]; +}; + struct amt_dev { struct net_device *dev; struct net_device *stream_dev; @@ -211,12 +246,19 @@ struct amt_dev { reserved:16; }; +#define AMT_TOS 0xc0 +#define AMT_IPHDR_OPTS 4 #define AMT_MAX_GROUP 32 #define AMT_MAX_SOURCE 128 #define AMT_HSIZE_SHIFT 8 #define AMT_HSIZE (1 << AMT_HSIZE_SHIFT) +#define AMT_DISCOVERY_TIMEOUT 5000 +#define AMT_INIT_REQ_TIMEOUT 1 #define AMT_INIT_QUERY_INTERVAL 125 +#define AMT_MAX_REQ_TIMEOUT 120 +#define AMT_MAX_REQ_COUNT 3 +#define AMT_SECRET_TIMEOUT 60000 #define IANA_AMT_UDP_PORT 2268 #define AMT_MAX_TUNNELS 128 #define AMT_MAX_REQS 128 @@ -232,4 +274,9 @@ static inline bool netif_is_amt(const struct net_device *dev) return dev->rtnl_link_ops && !strcmp(dev->rtnl_link_ops->kind, "amt"); } +static inline u64 amt_gmi(const struct amt_dev *amt) +{ + return ((amt->qrv * amt->qi) + amt->qri) * 1000; +} + #endif /* _NET_AMT_H_ */ |