| /* |
| * Common framework for low-level network console, dump, and debugger code |
| * |
| * Sep 8 2003 Matt Mackall <mpm@selenic.com> |
| * |
| * based on the netconsole code from: |
| * |
| * Copyright (C) 2001 Ingo Molnar <mingo@redhat.com> |
| * Copyright (C) 2002 Red Hat, Inc. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/moduleparam.h> |
| #include <linux/kernel.h> |
| #include <linux/netdevice.h> |
| #include <linux/etherdevice.h> |
| #include <linux/string.h> |
| #include <linux/if_arp.h> |
| #include <linux/inetdevice.h> |
| #include <linux/inet.h> |
| #include <linux/interrupt.h> |
| #include <linux/netpoll.h> |
| #include <linux/sched.h> |
| #include <linux/delay.h> |
| #include <linux/rcupdate.h> |
| #include <linux/workqueue.h> |
| #include <linux/slab.h> |
| #include <linux/export.h> |
| #include <linux/if_vlan.h> |
| #include <net/tcp.h> |
| #include <net/udp.h> |
| #include <net/addrconf.h> |
| #include <net/ndisc.h> |
| #include <net/ip6_checksum.h> |
| #include <asm/unaligned.h> |
| #include <trace/events/napi.h> |
| |
| /* |
| * We maintain a small pool of fully-sized skbs, to make sure the |
| * message gets out even in extreme OOM situations. |
| */ |
| |
| #define MAX_UDP_CHUNK 1460 |
| #define MAX_SKBS 32 |
| |
| static struct sk_buff_head skb_pool; |
| |
| static atomic_t trapped; |
| |
| DEFINE_STATIC_SRCU(netpoll_srcu); |
| |
| #define USEC_PER_POLL 50 |
| #define NETPOLL_RX_ENABLED 1 |
| #define NETPOLL_RX_DROP 2 |
| |
| #define MAX_SKB_SIZE \ |
| (sizeof(struct ethhdr) + \ |
| sizeof(struct iphdr) + \ |
| sizeof(struct udphdr) + \ |
| MAX_UDP_CHUNK) |
| |
| static void zap_completion_queue(void); |
| static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo); |
| static void netpoll_async_cleanup(struct work_struct *work); |
| |
| static unsigned int carrier_timeout = 4; |
| module_param(carrier_timeout, uint, 0644); |
| |
| #define np_info(np, fmt, ...) \ |
| pr_info("%s: " fmt, np->name, ##__VA_ARGS__) |
| #define np_err(np, fmt, ...) \ |
| pr_err("%s: " fmt, np->name, ##__VA_ARGS__) |
| #define np_notice(np, fmt, ...) \ |
| pr_notice("%s: " fmt, np->name, ##__VA_ARGS__) |
| |
| static void queue_process(struct work_struct *work) |
| { |
| struct netpoll_info *npinfo = |
| container_of(work, struct netpoll_info, tx_work.work); |
| struct sk_buff *skb; |
| unsigned long flags; |
| |
| while ((skb = skb_dequeue(&npinfo->txq))) { |
| struct net_device *dev = skb->dev; |
| const struct net_device_ops *ops = dev->netdev_ops; |
| struct netdev_queue *txq; |
| |
| if (!netif_device_present(dev) || !netif_running(dev)) { |
| __kfree_skb(skb); |
| continue; |
| } |
| |
| txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb)); |
| |
| local_irq_save(flags); |
| __netif_tx_lock(txq, smp_processor_id()); |
| if (netif_xmit_frozen_or_stopped(txq) || |
| ops->ndo_start_xmit(skb, dev) != NETDEV_TX_OK) { |
| skb_queue_head(&npinfo->txq, skb); |
| __netif_tx_unlock(txq); |
| local_irq_restore(flags); |
| |
| schedule_delayed_work(&npinfo->tx_work, HZ/10); |
| return; |
| } |
| __netif_tx_unlock(txq); |
| local_irq_restore(flags); |
| } |
| } |
| |
| static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh, |
| unsigned short ulen, __be32 saddr, __be32 daddr) |
| { |
| __wsum psum; |
| |
| if (uh->check == 0 || skb_csum_unnecessary(skb)) |
| return 0; |
| |
| psum = csum_tcpudp_nofold(saddr, daddr, ulen, IPPROTO_UDP, 0); |
| |
| if (skb->ip_summed == CHECKSUM_COMPLETE && |
| !csum_fold(csum_add(psum, skb->csum))) |
| return 0; |
| |
| skb->csum = psum; |
| |
| return __skb_checksum_complete(skb); |
| } |
| |
| /* |
| * Check whether delayed processing was scheduled for our NIC. If so, |
| * we attempt to grab the poll lock and use ->poll() to pump the card. |
| * If this fails, either we've recursed in ->poll() or it's already |
| * running on another CPU. |
| * |
| * Note: we don't mask interrupts with this lock because we're using |
| * trylock here and interrupts are already disabled in the softirq |
| * case. Further, we test the poll_owner to avoid recursion on UP |
| * systems where the lock doesn't exist. |
| * |
| * In cases where there is bi-directional communications, reading only |
| * one message at a time can lead to packets being dropped by the |
| * network adapter, forcing superfluous retries and possibly timeouts. |
| * Thus, we set our budget to greater than 1. |
| */ |
| static int poll_one_napi(struct napi_struct *napi, int budget) |
| { |
| int work; |
| |
| /* net_rx_action's ->poll() invocations and our's are |
| * synchronized by this test which is only made while |
| * holding the napi->poll_lock. |
| */ |
| if (!test_bit(NAPI_STATE_SCHED, &napi->state)) |
| return budget; |
| |
| set_bit(NAPI_STATE_NPSVC, &napi->state); |
| |
| work = napi->poll(napi, budget); |
| trace_napi_poll(napi); |
| |
| clear_bit(NAPI_STATE_NPSVC, &napi->state); |
| |
| return budget - work; |
| } |
| |
| static void poll_napi(struct net_device *dev) |
| { |
| struct napi_struct *napi; |
| int budget = 16; |
| |
| list_for_each_entry(napi, &dev->napi_list, dev_list) { |
| if (napi->poll_owner != smp_processor_id() && |
| spin_trylock(&napi->poll_lock)) { |
| budget = poll_one_napi(napi, budget); |
| spin_unlock(&napi->poll_lock); |
| |
| if (!budget) |
| break; |
| } |
| } |
| } |
| |
| static void service_neigh_queue(struct netpoll_info *npi) |
| { |
| if (npi) { |
| struct sk_buff *skb; |
| |
| while ((skb = skb_dequeue(&npi->neigh_tx))) |
| netpoll_neigh_reply(skb, npi); |
| } |
| } |
| |
| static void netpoll_poll_dev(struct net_device *dev) |
| { |
| const struct net_device_ops *ops; |
| struct netpoll_info *ni = rcu_dereference_bh(dev->npinfo); |
| |
| /* Don't do any rx activity if the dev_lock mutex is held |
| * the dev_open/close paths use this to block netpoll activity |
| * while changing device state |
| */ |
| if (down_trylock(&ni->dev_lock)) |
| return; |
| |
| if (!netif_running(dev)) { |
| up(&ni->dev_lock); |
| return; |
| } |
| |
| ni->rx_flags |= NETPOLL_RX_DROP; |
| atomic_inc(&trapped); |
| |
| ops = dev->netdev_ops; |
| if (!ops->ndo_poll_controller) { |
| up(&ni->dev_lock); |
| return; |
| } |
| |
| /* Process pending work on NIC */ |
| ops->ndo_poll_controller(dev); |
| |
| poll_napi(dev); |
| |
| atomic_dec(&trapped); |
| ni->rx_flags &= ~NETPOLL_RX_DROP; |
| |
| up(&ni->dev_lock); |
| |
| if (dev->flags & IFF_SLAVE) { |
| if (ni) { |
| struct net_device *bond_dev; |
| struct sk_buff *skb; |
| struct netpoll_info *bond_ni; |
| |
| bond_dev = netdev_master_upper_dev_get_rcu(dev); |
| bond_ni = rcu_dereference_bh(bond_dev->npinfo); |
| while ((skb = skb_dequeue(&ni->neigh_tx))) { |
| skb->dev = bond_dev; |
| skb_queue_tail(&bond_ni->neigh_tx, skb); |
| } |
| } |
| } |
| |
| service_neigh_queue(ni); |
| |
| zap_completion_queue(); |
| } |
| |
| void netpoll_rx_disable(struct net_device *dev) |
| { |
| struct netpoll_info *ni; |
| int idx; |
| might_sleep(); |
| idx = srcu_read_lock(&netpoll_srcu); |
| ni = srcu_dereference(dev->npinfo, &netpoll_srcu); |
| if (ni) |
| down(&ni->dev_lock); |
| srcu_read_unlock(&netpoll_srcu, idx); |
| } |
| EXPORT_SYMBOL(netpoll_rx_disable); |
| |
| void netpoll_rx_enable(struct net_device *dev) |
| { |
| struct netpoll_info *ni; |
| rcu_read_lock(); |
| ni = rcu_dereference(dev->npinfo); |
| if (ni) |
| up(&ni->dev_lock); |
| rcu_read_unlock(); |
| } |
| EXPORT_SYMBOL(netpoll_rx_enable); |
| |
| static void refill_skbs(void) |
| { |
| struct sk_buff *skb; |
| unsigned long flags; |
| |
| spin_lock_irqsave(&skb_pool.lock, flags); |
| while (skb_pool.qlen < MAX_SKBS) { |
| skb = alloc_skb(MAX_SKB_SIZE, GFP_ATOMIC); |
| if (!skb) |
| break; |
| |
| __skb_queue_tail(&skb_pool, skb); |
| } |
| spin_unlock_irqrestore(&skb_pool.lock, flags); |
| } |
| |
| static void zap_completion_queue(void) |
| { |
| unsigned long flags; |
| struct softnet_data *sd = &get_cpu_var(softnet_data); |
| |
| if (sd->completion_queue) { |
| struct sk_buff *clist; |
| |
| local_irq_save(flags); |
| clist = sd->completion_queue; |
| sd->completion_queue = NULL; |
| local_irq_restore(flags); |
| |
| while (clist != NULL) { |
| struct sk_buff *skb = clist; |
| clist = clist->next; |
| if (skb->destructor) { |
| atomic_inc(&skb->users); |
| dev_kfree_skb_any(skb); /* put this one back */ |
| } else { |
| __kfree_skb(skb); |
| } |
| } |
| } |
| |
| put_cpu_var(softnet_data); |
| } |
| |
| static struct sk_buff *find_skb(struct netpoll *np, int len, int reserve) |
| { |
| int count = 0; |
| struct sk_buff *skb; |
| |
| zap_completion_queue(); |
| refill_skbs(); |
| repeat: |
| |
| skb = alloc_skb(len, GFP_ATOMIC); |
| if (!skb) |
| skb = skb_dequeue(&skb_pool); |
| |
| if (!skb) { |
| if (++count < 10) { |
| netpoll_poll_dev(np->dev); |
| goto repeat; |
| } |
| return NULL; |
| } |
| |
| atomic_set(&skb->users, 1); |
| skb_reserve(skb, reserve); |
| return skb; |
| } |
| |
| static int netpoll_owner_active(struct net_device *dev) |
| { |
| struct napi_struct *napi; |
| |
| list_for_each_entry(napi, &dev->napi_list, dev_list) { |
| if (napi->poll_owner == smp_processor_id()) |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* call with IRQ disabled */ |
| void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb, |
| struct net_device *dev) |
| { |
| int status = NETDEV_TX_BUSY; |
| unsigned long tries; |
| const struct net_device_ops *ops = dev->netdev_ops; |
| /* It is up to the caller to keep npinfo alive. */ |
| struct netpoll_info *npinfo; |
| |
| WARN_ON_ONCE(!irqs_disabled()); |
| |
| npinfo = rcu_dereference_bh(np->dev->npinfo); |
| if (!npinfo || !netif_running(dev) || !netif_device_present(dev)) { |
| __kfree_skb(skb); |
| return; |
| } |
| |
| /* don't get messages out of order, and no recursion */ |
| if (skb_queue_len(&npinfo->txq) == 0 && !netpoll_owner_active(dev)) { |
| struct netdev_queue *txq; |
| |
| txq = netdev_pick_tx(dev, skb, NULL); |
| |
| /* try until next clock tick */ |
| for (tries = jiffies_to_usecs(1)/USEC_PER_POLL; |
| tries > 0; --tries) { |
| if (__netif_tx_trylock(txq)) { |
| if (!netif_xmit_stopped(txq)) { |
| if (vlan_tx_tag_present(skb) && |
| !vlan_hw_offload_capable(netif_skb_features(skb), |
| skb->vlan_proto)) { |
| skb = __vlan_put_tag(skb, skb->vlan_proto, vlan_tx_tag_get(skb)); |
| if (unlikely(!skb)) { |
| /* This is actually a packet drop, but we |
| * don't want the code at the end of this |
| * function to try and re-queue a NULL skb. |
| */ |
| status = NETDEV_TX_OK; |
| goto unlock_txq; |
| } |
| skb->vlan_tci = 0; |
| } |
| |
| status = ops->ndo_start_xmit(skb, dev); |
| if (status == NETDEV_TX_OK) |
| txq_trans_update(txq); |
| } |
| unlock_txq: |
| __netif_tx_unlock(txq); |
| |
| if (status == NETDEV_TX_OK) |
| break; |
| |
| } |
| |
| /* tickle device maybe there is some cleanup */ |
| netpoll_poll_dev(np->dev); |
| |
| udelay(USEC_PER_POLL); |
| } |
| |
| WARN_ONCE(!irqs_disabled(), |
| "netpoll_send_skb_on_dev(): %s enabled interrupts in poll (%pF)\n", |
| dev->name, ops->ndo_start_xmit); |
| |
| } |
| |
| if (status != NETDEV_TX_OK) { |
| skb_queue_tail(&npinfo->txq, skb); |
| schedule_delayed_work(&npinfo->tx_work,0); |
| } |
| } |
| EXPORT_SYMBOL(netpoll_send_skb_on_dev); |
| |
| void netpoll_send_udp(struct netpoll *np, const char *msg, int len) |
| { |
| int total_len, ip_len, udp_len; |
| struct sk_buff *skb; |
| struct udphdr *udph; |
| struct iphdr *iph; |
| struct ethhdr *eth; |
| static atomic_t ip_ident; |
| struct ipv6hdr *ip6h; |
| |
| udp_len = len + sizeof(*udph); |
| if (np->ipv6) |
| ip_len = udp_len + sizeof(*ip6h); |
| else |
| ip_len = udp_len + sizeof(*iph); |
| |
| total_len = ip_len + LL_RESERVED_SPACE(np->dev); |
| |
| skb = find_skb(np, total_len + np->dev->needed_tailroom, |
| total_len - len); |
| if (!skb) |
| return; |
| |
| skb_copy_to_linear_data(skb, msg, len); |
| skb_put(skb, len); |
| |
| skb_push(skb, sizeof(*udph)); |
| skb_reset_transport_header(skb); |
| udph = udp_hdr(skb); |
| udph->source = htons(np->local_port); |
| udph->dest = htons(np->remote_port); |
| udph->len = htons(udp_len); |
| |
| if (np->ipv6) { |
| udph->check = 0; |
| udph->check = csum_ipv6_magic(&np->local_ip.in6, |
| &np->remote_ip.in6, |
| udp_len, IPPROTO_UDP, |
| csum_partial(udph, udp_len, 0)); |
| if (udph->check == 0) |
| udph->check = CSUM_MANGLED_0; |
| |
| skb_push(skb, sizeof(*ip6h)); |
| skb_reset_network_header(skb); |
| ip6h = ipv6_hdr(skb); |
| |
| /* ip6h->version = 6; ip6h->priority = 0; */ |
| put_unaligned(0x60, (unsigned char *)ip6h); |
| ip6h->flow_lbl[0] = 0; |
| ip6h->flow_lbl[1] = 0; |
| ip6h->flow_lbl[2] = 0; |
| |
| ip6h->payload_len = htons(sizeof(struct udphdr) + len); |
| ip6h->nexthdr = IPPROTO_UDP; |
| ip6h->hop_limit = 32; |
| ip6h->saddr = np->local_ip.in6; |
| ip6h->daddr = np->remote_ip.in6; |
| |
| eth = (struct ethhdr *) skb_push(skb, ETH_HLEN); |
| skb_reset_mac_header(skb); |
| skb->protocol = eth->h_proto = htons(ETH_P_IPV6); |
| } else { |
| udph->check = 0; |
| udph->check = csum_tcpudp_magic(np->local_ip.ip, |
| np->remote_ip.ip, |
| udp_len, IPPROTO_UDP, |
| csum_partial(udph, udp_len, 0)); |
| if (udph->check == 0) |
| udph->check = CSUM_MANGLED_0; |
| |
| skb_push(skb, sizeof(*iph)); |
| skb_reset_network_header(skb); |
| iph = ip_hdr(skb); |
| |
| /* iph->version = 4; iph->ihl = 5; */ |
| put_unaligned(0x45, (unsigned char *)iph); |
| iph->tos = 0; |
| put_unaligned(htons(ip_len), &(iph->tot_len)); |
| iph->id = htons(atomic_inc_return(&ip_ident)); |
| iph->frag_off = 0; |
| iph->ttl = 64; |
| iph->protocol = IPPROTO_UDP; |
| iph->check = 0; |
| put_unaligned(np->local_ip.ip, &(iph->saddr)); |
| put_unaligned(np->remote_ip.ip, &(iph->daddr)); |
| iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); |
| |
| eth = (struct ethhdr *) skb_push(skb, ETH_HLEN); |
| skb_reset_mac_header(skb); |
| skb->protocol = eth->h_proto = htons(ETH_P_IP); |
| } |
| |
| ether_addr_copy(eth->h_source, np->dev->dev_addr); |
| ether_addr_copy(eth->h_dest, np->remote_mac); |
| |
| skb->dev = np->dev; |
| |
| netpoll_send_skb(np, skb); |
| } |
| EXPORT_SYMBOL(netpoll_send_udp); |
| |
| static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo) |
| { |
| int size, type = ARPOP_REPLY; |
| __be32 sip, tip; |
| unsigned char *sha; |
| struct sk_buff *send_skb; |
| struct netpoll *np, *tmp; |
| unsigned long flags; |
| int hlen, tlen; |
| int hits = 0, proto; |
| |
| if (list_empty(&npinfo->rx_np)) |
| return; |
| |
| /* Before checking the packet, we do some early |
| inspection whether this is interesting at all */ |
| spin_lock_irqsave(&npinfo->rx_lock, flags); |
| list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) { |
| if (np->dev == skb->dev) |
| hits++; |
| } |
| spin_unlock_irqrestore(&npinfo->rx_lock, flags); |
| |
| /* No netpoll struct is using this dev */ |
| if (!hits) |
| return; |
| |
| proto = ntohs(eth_hdr(skb)->h_proto); |
| if (proto == ETH_P_ARP) { |
| struct arphdr *arp; |
| unsigned char *arp_ptr; |
| /* No arp on this interface */ |
| if (skb->dev->flags & IFF_NOARP) |
| return; |
| |
| if (!pskb_may_pull(skb, arp_hdr_len(skb->dev))) |
| return; |
| |
| skb_reset_network_header(skb); |
| skb_reset_transport_header(skb); |
| arp = arp_hdr(skb); |
| |
| if ((arp->ar_hrd != htons(ARPHRD_ETHER) && |
| arp->ar_hrd != htons(ARPHRD_IEEE802)) || |
| arp->ar_pro != htons(ETH_P_IP) || |
| arp->ar_op != htons(ARPOP_REQUEST)) |
| return; |
| |
| arp_ptr = (unsigned char *)(arp+1); |
| /* save the location of the src hw addr */ |
| sha = arp_ptr; |
| arp_ptr += skb->dev->addr_len; |
| memcpy(&sip, arp_ptr, 4); |
| arp_ptr += 4; |
| /* If we actually cared about dst hw addr, |
| it would get copied here */ |
| arp_ptr += skb->dev->addr_len; |
| memcpy(&tip, arp_ptr, 4); |
| |
| /* Should we ignore arp? */ |
| if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip)) |
| return; |
| |
| size = arp_hdr_len(skb->dev); |
| |
| spin_lock_irqsave(&npinfo->rx_lock, flags); |
| list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) { |
| if (tip != np->local_ip.ip) |
| continue; |
| |
| hlen = LL_RESERVED_SPACE(np->dev); |
| tlen = np->dev->needed_tailroom; |
| send_skb = find_skb(np, size + hlen + tlen, hlen); |
| if (!send_skb) |
| continue; |
| |
| skb_reset_network_header(send_skb); |
| arp = (struct arphdr *) skb_put(send_skb, size); |
| send_skb->dev = skb->dev; |
| send_skb->protocol = htons(ETH_P_ARP); |
| |
| /* Fill the device header for the ARP frame */ |
| if (dev_hard_header(send_skb, skb->dev, ETH_P_ARP, |
| sha, np->dev->dev_addr, |
| send_skb->len) < 0) { |
| kfree_skb(send_skb); |
| continue; |
| } |
| |
| /* |
| * Fill out the arp protocol part. |
| * |
| * we only support ethernet device type, |
| * which (according to RFC 1390) should |
| * always equal 1 (Ethernet). |
| */ |
| |
| arp->ar_hrd = htons(np->dev->type); |
| arp->ar_pro = htons(ETH_P_IP); |
| arp->ar_hln = np->dev->addr_len; |
| arp->ar_pln = 4; |
| arp->ar_op = htons(type); |
| |
| arp_ptr = (unsigned char *)(arp + 1); |
| memcpy(arp_ptr, np->dev->dev_addr, np->dev->addr_len); |
| arp_ptr += np->dev->addr_len; |
| memcpy(arp_ptr, &tip, 4); |
| arp_ptr += 4; |
| memcpy(arp_ptr, sha, np->dev->addr_len); |
| arp_ptr += np->dev->addr_len; |
| memcpy(arp_ptr, &sip, 4); |
| |
| netpoll_send_skb(np, send_skb); |
| |
| /* If there are several rx_skb_hooks for the same |
| * address we're fine by sending a single reply |
| */ |
| break; |
| } |
| spin_unlock_irqrestore(&npinfo->rx_lock, flags); |
| } else if( proto == ETH_P_IPV6) { |
| #if IS_ENABLED(CONFIG_IPV6) |
| struct nd_msg *msg; |
| u8 *lladdr = NULL; |
| struct ipv6hdr *hdr; |
| struct icmp6hdr *icmp6h; |
| const struct in6_addr *saddr; |
| const struct in6_addr *daddr; |
| struct inet6_dev *in6_dev = NULL; |
| struct in6_addr *target; |
| |
| in6_dev = in6_dev_get(skb->dev); |
| if (!in6_dev || !in6_dev->cnf.accept_ra) |
| return; |
| |
| if (!pskb_may_pull(skb, skb->len)) |
| return; |
| |
| msg = (struct nd_msg *)skb_transport_header(skb); |
| |
| __skb_push(skb, skb->data - skb_transport_header(skb)); |
| |
| if (ipv6_hdr(skb)->hop_limit != 255) |
| return; |
| if (msg->icmph.icmp6_code != 0) |
| return; |
| if (msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION) |
| return; |
| |
| saddr = &ipv6_hdr(skb)->saddr; |
| daddr = &ipv6_hdr(skb)->daddr; |
| |
| size = sizeof(struct icmp6hdr) + sizeof(struct in6_addr); |
| |
| spin_lock_irqsave(&npinfo->rx_lock, flags); |
| list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) { |
| if (!ipv6_addr_equal(daddr, &np->local_ip.in6)) |
| continue; |
| |
| hlen = LL_RESERVED_SPACE(np->dev); |
| tlen = np->dev->needed_tailroom; |
| send_skb = find_skb(np, size + hlen + tlen, hlen); |
| if (!send_skb) |
| continue; |
| |
| send_skb->protocol = htons(ETH_P_IPV6); |
| send_skb->dev = skb->dev; |
| |
| skb_reset_network_header(send_skb); |
| hdr = (struct ipv6hdr *) skb_put(send_skb, sizeof(struct ipv6hdr)); |
| *(__be32*)hdr = htonl(0x60000000); |
| hdr->payload_len = htons(size); |
| hdr->nexthdr = IPPROTO_ICMPV6; |
| hdr->hop_limit = 255; |
| hdr->saddr = *saddr; |
| hdr->daddr = *daddr; |
| |
| icmp6h = (struct icmp6hdr *) skb_put(send_skb, sizeof(struct icmp6hdr)); |
| icmp6h->icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT; |
| icmp6h->icmp6_router = 0; |
| icmp6h->icmp6_solicited = 1; |
| |
| target = (struct in6_addr *) skb_put(send_skb, sizeof(struct in6_addr)); |
| *target = msg->target; |
| icmp6h->icmp6_cksum = csum_ipv6_magic(saddr, daddr, size, |
| IPPROTO_ICMPV6, |
| csum_partial(icmp6h, |
| size, 0)); |
| |
| if (dev_hard_header(send_skb, skb->dev, ETH_P_IPV6, |
| lladdr, np->dev->dev_addr, |
| send_skb->len) < 0) { |
| kfree_skb(send_skb); |
| continue; |
| } |
| |
| netpoll_send_skb(np, send_skb); |
| |
| /* If there are several rx_skb_hooks for the same |
| * address, we're fine by sending a single reply |
| */ |
| break; |
| } |
| spin_unlock_irqrestore(&npinfo->rx_lock, flags); |
| #endif |
| } |
| } |
| |
| static bool pkt_is_ns(struct sk_buff *skb) |
| { |
| struct nd_msg *msg; |
| struct ipv6hdr *hdr; |
| |
| if (skb->protocol != htons(ETH_P_ARP)) |
| return false; |
| if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + sizeof(struct nd_msg))) |
| return false; |
| |
| msg = (struct nd_msg *)skb_transport_header(skb); |
| __skb_push(skb, skb->data - skb_transport_header(skb)); |
| hdr = ipv6_hdr(skb); |
| |
| if (hdr->nexthdr != IPPROTO_ICMPV6) |
| return false; |
| if (hdr->hop_limit != 255) |
| return false; |
| if (msg->icmph.icmp6_code != 0) |
| return false; |
| if (msg->icmph.icmp6_type != NDISC_NEIGHBOUR_SOLICITATION) |
| return false; |
| |
| return true; |
| } |
| |
| int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo) |
| { |
| int proto, len, ulen, data_len; |
| int hits = 0, offset; |
| const struct iphdr *iph; |
| struct udphdr *uh; |
| struct netpoll *np, *tmp; |
| uint16_t source; |
| |
| if (list_empty(&npinfo->rx_np)) |
| goto out; |
| |
| if (skb->dev->type != ARPHRD_ETHER) |
| goto out; |
| |
| /* check if netpoll clients need ARP */ |
| if (skb->protocol == htons(ETH_P_ARP) && atomic_read(&trapped)) { |
| skb_queue_tail(&npinfo->neigh_tx, skb); |
| return 1; |
| } else if (pkt_is_ns(skb) && atomic_read(&trapped)) { |
| skb_queue_tail(&npinfo->neigh_tx, skb); |
| return 1; |
| } |
| |
| if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) { |
| skb = vlan_untag(skb); |
| if (unlikely(!skb)) |
| goto out; |
| } |
| |
| proto = ntohs(eth_hdr(skb)->h_proto); |
| if (proto != ETH_P_IP && proto != ETH_P_IPV6) |
| goto out; |
| if (skb->pkt_type == PACKET_OTHERHOST) |
| goto out; |
| if (skb_shared(skb)) |
| goto out; |
| |
| if (proto == ETH_P_IP) { |
| if (!pskb_may_pull(skb, sizeof(struct iphdr))) |
| goto out; |
| iph = (struct iphdr *)skb->data; |
| if (iph->ihl < 5 || iph->version != 4) |
| goto out; |
| if (!pskb_may_pull(skb, iph->ihl*4)) |
| goto out; |
| iph = (struct iphdr *)skb->data; |
| if (ip_fast_csum((u8 *)iph, iph->ihl) != 0) |
| goto out; |
| |
| len = ntohs(iph->tot_len); |
| if (skb->len < len || len < iph->ihl*4) |
| goto out; |
| |
| /* |
| * Our transport medium may have padded the buffer out. |
| * Now We trim to the true length of the frame. |
| */ |
| if (pskb_trim_rcsum(skb, len)) |
| goto out; |
| |
| iph = (struct iphdr *)skb->data; |
| if (iph->protocol != IPPROTO_UDP) |
| goto out; |
| |
| len -= iph->ihl*4; |
| uh = (struct udphdr *)(((char *)iph) + iph->ihl*4); |
| offset = (unsigned char *)(uh + 1) - skb->data; |
| ulen = ntohs(uh->len); |
| data_len = skb->len - offset; |
| source = ntohs(uh->source); |
| |
| if (ulen != len) |
| goto out; |
| if (checksum_udp(skb, uh, ulen, iph->saddr, iph->daddr)) |
| goto out; |
| list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) { |
| if (np->local_ip.ip && np->local_ip.ip != iph->daddr) |
| continue; |
| if (np->remote_ip.ip && np->remote_ip.ip != iph->saddr) |
| continue; |
| if (np->local_port && np->local_port != ntohs(uh->dest)) |
| continue; |
| |
| np->rx_skb_hook(np, source, skb, offset, data_len); |
| hits++; |
| } |
| } else { |
| #if IS_ENABLED(CONFIG_IPV6) |
| const struct ipv6hdr *ip6h; |
| |
| if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) |
| goto out; |
| ip6h = (struct ipv6hdr *)skb->data; |
| if (ip6h->version != 6) |
| goto out; |
| len = ntohs(ip6h->payload_len); |
| if (!len) |
| goto out; |
| if (len + sizeof(struct ipv6hdr) > skb->len) |
| goto out; |
| if (pskb_trim_rcsum(skb, len + sizeof(struct ipv6hdr))) |
| goto out; |
| ip6h = ipv6_hdr(skb); |
| if (!pskb_may_pull(skb, sizeof(struct udphdr))) |
| goto out; |
| uh = udp_hdr(skb); |
| offset = (unsigned char *)(uh + 1) - skb->data; |
| ulen = ntohs(uh->len); |
| data_len = skb->len - offset; |
| source = ntohs(uh->source); |
| if (ulen != skb->len) |
| goto out; |
| if (udp6_csum_init(skb, uh, IPPROTO_UDP)) |
| goto out; |
| list_for_each_entry_safe(np, tmp, &npinfo->rx_np, rx) { |
| if (!ipv6_addr_equal(&np->local_ip.in6, &ip6h->daddr)) |
| continue; |
| if (!ipv6_addr_equal(&np->remote_ip.in6, &ip6h->saddr)) |
| continue; |
| if (np->local_port && np->local_port != ntohs(uh->dest)) |
| continue; |
| |
| np->rx_skb_hook(np, source, skb, offset, data_len); |
| hits++; |
| } |
| #endif |
| } |
| |
| if (!hits) |
| goto out; |
| |
| kfree_skb(skb); |
| return 1; |
| |
| out: |
| if (atomic_read(&trapped)) { |
| kfree_skb(skb); |
| return 1; |
| } |
| |
| return 0; |
| } |
| |
| void netpoll_print_options(struct netpoll *np) |
| { |
| np_info(np, "local port %d\n", np->local_port); |
| if (np->ipv6) |
| np_info(np, "local IPv6 address %pI6c\n", &np->local_ip.in6); |
| else |
| np_info(np, "local IPv4 address %pI4\n", &np->local_ip.ip); |
| np_info(np, "interface '%s'\n", np->dev_name); |
| np_info(np, "remote port %d\n", np->remote_port); |
| if (np->ipv6) |
| np_info(np, "remote IPv6 address %pI6c\n", &np->remote_ip.in6); |
| else |
| np_info(np, "remote IPv4 address %pI4\n", &np->remote_ip.ip); |
| np_info(np, "remote ethernet address %pM\n", np->remote_mac); |
| } |
| EXPORT_SYMBOL(netpoll_print_options); |
| |
| static int netpoll_parse_ip_addr(const char *str, union inet_addr *addr) |
| { |
| const char *end; |
| |
| if (!strchr(str, ':') && |
| in4_pton(str, -1, (void *)addr, -1, &end) > 0) { |
| if (!*end) |
| return 0; |
| } |
| if (in6_pton(str, -1, addr->in6.s6_addr, -1, &end) > 0) { |
| #if IS_ENABLED(CONFIG_IPV6) |
| if (!*end) |
| return 1; |
| #else |
| return -1; |
| #endif |
| } |
| return -1; |
| } |
| |
| int netpoll_parse_options(struct netpoll *np, char *opt) |
| { |
| char *cur=opt, *delim; |
| int ipv6; |
| bool ipversion_set = false; |
| |
| if (*cur != '@') { |
| if ((delim = strchr(cur, '@')) == NULL) |
| goto parse_failed; |
| *delim = 0; |
| if (kstrtou16(cur, 10, &np->local_port)) |
| goto parse_failed; |
| cur = delim; |
| } |
| cur++; |
| |
| if (*cur != '/') { |
| ipversion_set = true; |
| if ((delim = strchr(cur, '/')) == NULL) |
| goto parse_failed; |
| *delim = 0; |
| ipv6 = netpoll_parse_ip_addr(cur, &np->local_ip); |
| if (ipv6 < 0) |
| goto parse_failed; |
| else |
| np->ipv6 = (bool)ipv6; |
| cur = delim; |
| } |
| cur++; |
| |
| if (*cur != ',') { |
| /* parse out dev name */ |
| if ((delim = strchr(cur, ',')) == NULL) |
| goto parse_failed; |
| *delim = 0; |
| strlcpy(np->dev_name, cur, sizeof(np->dev_name)); |
| cur = delim; |
| } |
| cur++; |
| |
| if (*cur != '@') { |
| /* dst port */ |
| if ((delim = strchr(cur, '@')) == NULL) |
| goto parse_failed; |
| *delim = 0; |
| if (*cur == ' ' || *cur == '\t') |
| np_info(np, "warning: whitespace is not allowed\n"); |
| if (kstrtou16(cur, 10, &np->remote_port)) |
| goto parse_failed; |
| cur = delim; |
| } |
| cur++; |
| |
| /* dst ip */ |
| if ((delim = strchr(cur, '/')) == NULL) |
| goto parse_failed; |
| *delim = 0; |
| ipv6 = netpoll_parse_ip_addr(cur, &np->remote_ip); |
| if (ipv6 < 0) |
| goto parse_failed; |
| else if (ipversion_set && np->ipv6 != (bool)ipv6) |
| goto parse_failed; |
| else |
| np->ipv6 = (bool)ipv6; |
| cur = delim + 1; |
| |
| if (*cur != 0) { |
| /* MAC address */ |
| if (!mac_pton(cur, np->remote_mac)) |
| goto parse_failed; |
| } |
| |
| netpoll_print_options(np); |
| |
| return 0; |
| |
| parse_failed: |
| np_info(np, "couldn't parse config at '%s'!\n", cur); |
| return -1; |
| } |
| EXPORT_SYMBOL(netpoll_parse_options); |
| |
| int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp) |
| { |
| struct netpoll_info *npinfo; |
| const struct net_device_ops *ops; |
| unsigned long flags; |
| int err; |
| |
| np->dev = ndev; |
| strlcpy(np->dev_name, ndev->name, IFNAMSIZ); |
| INIT_WORK(&np->cleanup_work, netpoll_async_cleanup); |
| |
| if ((ndev->priv_flags & IFF_DISABLE_NETPOLL) || |
| !ndev->netdev_ops->ndo_poll_controller) { |
| np_err(np, "%s doesn't support polling, aborting\n", |
| np->dev_name); |
| err = -ENOTSUPP; |
| goto out; |
| } |
| |
| if (!ndev->npinfo) { |
| npinfo = kmalloc(sizeof(*npinfo), gfp); |
| if (!npinfo) { |
| err = -ENOMEM; |
| goto out; |
| } |
| |
| npinfo->rx_flags = 0; |
| INIT_LIST_HEAD(&npinfo->rx_np); |
| |
| spin_lock_init(&npinfo->rx_lock); |
| sema_init(&npinfo->dev_lock, 1); |
| skb_queue_head_init(&npinfo->neigh_tx); |
| skb_queue_head_init(&npinfo->txq); |
| INIT_DELAYED_WORK(&npinfo->tx_work, queue_process); |
| |
| atomic_set(&npinfo->refcnt, 1); |
| |
| ops = np->dev->netdev_ops; |
| if (ops->ndo_netpoll_setup) { |
| err = ops->ndo_netpoll_setup(ndev, npinfo, gfp); |
| if (err) |
| goto free_npinfo; |
| } |
| } else { |
| npinfo = rtnl_dereference(ndev->npinfo); |
| atomic_inc(&npinfo->refcnt); |
| } |
| |
| npinfo->netpoll = np; |
| |
| if (np->rx_skb_hook) { |
| spin_lock_irqsave(&npinfo->rx_lock, flags); |
| npinfo->rx_flags |= NETPOLL_RX_ENABLED; |
| list_add_tail(&np->rx, &npinfo->rx_np); |
| spin_unlock_irqrestore(&npinfo->rx_lock, flags); |
| } |
| |
| /* last thing to do is link it to the net device structure */ |
| rcu_assign_pointer(ndev->npinfo, npinfo); |
| |
| return 0; |
| |
| free_npinfo: |
| kfree(npinfo); |
| out: |
| return err; |
| } |
| EXPORT_SYMBOL_GPL(__netpoll_setup); |
| |
| int netpoll_setup(struct netpoll *np) |
| { |
| struct net_device *ndev = NULL; |
| struct in_device *in_dev; |
| int err; |
| |
| rtnl_lock(); |
| if (np->dev_name) { |
| struct net *net = current->nsproxy->net_ns; |
| ndev = __dev_get_by_name(net, np->dev_name); |
| } |
| if (!ndev) { |
| np_err(np, "%s doesn't exist, aborting\n", np->dev_name); |
| err = -ENODEV; |
| goto unlock; |
| } |
| dev_hold(ndev); |
| |
| if (netdev_master_upper_dev_get(ndev)) { |
| np_err(np, "%s is a slave device, aborting\n", np->dev_name); |
| err = -EBUSY; |
| goto put; |
| } |
| |
| if (!netif_running(ndev)) { |
| unsigned long atmost, atleast; |
| |
| np_info(np, "device %s not up yet, forcing it\n", np->dev_name); |
| |
| err = dev_open(ndev); |
| |
| if (err) { |
| np_err(np, "failed to open %s\n", ndev->name); |
| goto put; |
| } |
| |
| rtnl_unlock(); |
| atleast = jiffies + HZ/10; |
| atmost = jiffies + carrier_timeout * HZ; |
| while (!netif_carrier_ok(ndev)) { |
| if (time_after(jiffies, atmost)) { |
| np_notice(np, "timeout waiting for carrier\n"); |
| break; |
| } |
| msleep(1); |
| } |
| |
| /* If carrier appears to come up instantly, we don't |
| * trust it and pause so that we don't pump all our |
| * queued console messages into the bitbucket. |
| */ |
| |
| if (time_before(jiffies, atleast)) { |
| np_notice(np, "carrier detect appears untrustworthy, waiting 4 seconds\n"); |
| msleep(4000); |
| } |
| rtnl_lock(); |
| } |
| |
| if (!np->local_ip.ip) { |
| if (!np->ipv6) { |
| in_dev = __in_dev_get_rtnl(ndev); |
| |
| if (!in_dev || !in_dev->ifa_list) { |
| np_err(np, "no IP address for %s, aborting\n", |
| np->dev_name); |
| err = -EDESTADDRREQ; |
| goto put; |
| } |
| |
| np->local_ip.ip = in_dev->ifa_list->ifa_local; |
| np_info(np, "local IP %pI4\n", &np->local_ip.ip); |
| } else { |
| #if IS_ENABLED(CONFIG_IPV6) |
| struct inet6_dev *idev; |
| |
| err = -EDESTADDRREQ; |
| idev = __in6_dev_get(ndev); |
| if (idev) { |
| struct inet6_ifaddr *ifp; |
| |
| read_lock_bh(&idev->lock); |
| list_for_each_entry(ifp, &idev->addr_list, if_list) { |
| if (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL) |
| continue; |
| np->local_ip.in6 = ifp->addr; |
| err = 0; |
| break; |
| } |
| read_unlock_bh(&idev->lock); |
| } |
| if (err) { |
| np_err(np, "no IPv6 address for %s, aborting\n", |
| np->dev_name); |
| goto put; |
| } else |
| np_info(np, "local IPv6 %pI6c\n", &np->local_ip.in6); |
| #else |
| np_err(np, "IPv6 is not supported %s, aborting\n", |
| np->dev_name); |
| err = -EINVAL; |
| goto put; |
| #endif |
| } |
| } |
| |
| /* fill up the skb queue */ |
| refill_skbs(); |
| |
| err = __netpoll_setup(np, ndev, GFP_KERNEL); |
| if (err) |
| goto put; |
| |
| rtnl_unlock(); |
| return 0; |
| |
| put: |
| dev_put(ndev); |
| unlock: |
| rtnl_unlock(); |
| return err; |
| } |
| EXPORT_SYMBOL(netpoll_setup); |
| |
| static int __init netpoll_init(void) |
| { |
| skb_queue_head_init(&skb_pool); |
| return 0; |
| } |
| core_initcall(netpoll_init); |
| |
| static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head) |
| { |
| struct netpoll_info *npinfo = |
| container_of(rcu_head, struct netpoll_info, rcu); |
| |
| skb_queue_purge(&npinfo->neigh_tx); |
| skb_queue_purge(&npinfo->txq); |
| |
| /* we can't call cancel_delayed_work_sync here, as we are in softirq */ |
| cancel_delayed_work(&npinfo->tx_work); |
| |
| /* clean after last, unfinished work */ |
| __skb_queue_purge(&npinfo->txq); |
| /* now cancel it again */ |
| cancel_delayed_work(&npinfo->tx_work); |
| kfree(npinfo); |
| } |
| |
| void __netpoll_cleanup(struct netpoll *np) |
| { |
| struct netpoll_info *npinfo; |
| unsigned long flags; |
| |
| /* rtnl_dereference would be preferable here but |
| * rcu_cleanup_netpoll path can put us in here safely without |
| * holding the rtnl, so plain rcu_dereference it is |
| */ |
| npinfo = rtnl_dereference(np->dev->npinfo); |
| if (!npinfo) |
| return; |
| |
| if (!list_empty(&npinfo->rx_np)) { |
| spin_lock_irqsave(&npinfo->rx_lock, flags); |
| list_del(&np->rx); |
| if (list_empty(&npinfo->rx_np)) |
| npinfo->rx_flags &= ~NETPOLL_RX_ENABLED; |
| spin_unlock_irqrestore(&npinfo->rx_lock, flags); |
| } |
| |
| synchronize_srcu(&netpoll_srcu); |
| |
| if (atomic_dec_and_test(&npinfo->refcnt)) { |
| const struct net_device_ops *ops; |
| |
| ops = np->dev->netdev_ops; |
| if (ops->ndo_netpoll_cleanup) |
| ops->ndo_netpoll_cleanup(np->dev); |
| |
| rcu_assign_pointer(np->dev->npinfo, NULL); |
| call_rcu_bh(&npinfo->rcu, rcu_cleanup_netpoll_info); |
| } |
| } |
| EXPORT_SYMBOL_GPL(__netpoll_cleanup); |
| |
| static void netpoll_async_cleanup(struct work_struct *work) |
| { |
| struct netpoll *np = container_of(work, struct netpoll, cleanup_work); |
| |
| rtnl_lock(); |
| __netpoll_cleanup(np); |
| rtnl_unlock(); |
| kfree(np); |
| } |
| |
| void __netpoll_free_async(struct netpoll *np) |
| { |
| schedule_work(&np->cleanup_work); |
| } |
| EXPORT_SYMBOL_GPL(__netpoll_free_async); |
| |
| void netpoll_cleanup(struct netpoll *np) |
| { |
| rtnl_lock(); |
| if (!np->dev) |
| goto out; |
| __netpoll_cleanup(np); |
| dev_put(np->dev); |
| np->dev = NULL; |
| out: |
| rtnl_unlock(); |
| } |
| EXPORT_SYMBOL(netpoll_cleanup); |
| |
| int netpoll_trap(void) |
| { |
| return atomic_read(&trapped); |
| } |
| EXPORT_SYMBOL(netpoll_trap); |
| |
| void netpoll_set_trap(int trap) |
| { |
| if (trap) |
| atomic_inc(&trapped); |
| else |
| atomic_dec(&trapped); |
| } |
| EXPORT_SYMBOL(netpoll_set_trap); |