Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 1 | #include <linux/module.h> |
| 2 | #include <linux/kernel.h> |
| 3 | #include <linux/netdevice.h> |
| 4 | #include <linux/netlink.h> |
| 5 | #include <net/net_namespace.h> |
| 6 | #include <linux/if_arp.h> |
Jiri Pirko | 7e6d4da | 2013-07-02 10:55:31 +0200 | [diff] [blame] | 7 | #include <net/rtnetlink.h> |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 8 | |
| 9 | struct pcpu_lstats { |
| 10 | u64 packets; |
| 11 | u64 bytes; |
| 12 | struct u64_stats_sync syncp; |
| 13 | }; |
| 14 | |
| 15 | static netdev_tx_t nlmon_xmit(struct sk_buff *skb, struct net_device *dev) |
| 16 | { |
| 17 | int len = skb->len; |
| 18 | struct pcpu_lstats *stats = this_cpu_ptr(dev->lstats); |
| 19 | |
| 20 | u64_stats_update_begin(&stats->syncp); |
| 21 | stats->bytes += len; |
| 22 | stats->packets++; |
| 23 | u64_stats_update_end(&stats->syncp); |
| 24 | |
| 25 | dev_kfree_skb(skb); |
| 26 | |
| 27 | return NETDEV_TX_OK; |
| 28 | } |
| 29 | |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 30 | static int nlmon_dev_init(struct net_device *dev) |
| 31 | { |
WANG Cong | 1c213bd | 2014-02-13 11:46:28 -0800 | [diff] [blame] | 32 | dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats); |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 33 | return dev->lstats == NULL ? -ENOMEM : 0; |
| 34 | } |
| 35 | |
| 36 | static void nlmon_dev_uninit(struct net_device *dev) |
| 37 | { |
| 38 | free_percpu(dev->lstats); |
| 39 | } |
| 40 | |
Jiri Pirko | 7e6d4da | 2013-07-02 10:55:31 +0200 | [diff] [blame] | 41 | struct nlmon { |
| 42 | struct netlink_tap nt; |
| 43 | }; |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 44 | |
| 45 | static int nlmon_open(struct net_device *dev) |
| 46 | { |
Jiri Pirko | 7e6d4da | 2013-07-02 10:55:31 +0200 | [diff] [blame] | 47 | struct nlmon *nlmon = netdev_priv(dev); |
| 48 | |
| 49 | nlmon->nt.dev = dev; |
| 50 | nlmon->nt.module = THIS_MODULE; |
| 51 | return netlink_add_tap(&nlmon->nt); |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 52 | } |
| 53 | |
| 54 | static int nlmon_close(struct net_device *dev) |
| 55 | { |
Jiri Pirko | 7e6d4da | 2013-07-02 10:55:31 +0200 | [diff] [blame] | 56 | struct nlmon *nlmon = netdev_priv(dev); |
| 57 | |
| 58 | return netlink_remove_tap(&nlmon->nt); |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 59 | } |
| 60 | |
stephen hemminger | bc1f447 | 2017-01-06 19:12:52 -0800 | [diff] [blame] | 61 | static void |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 62 | nlmon_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats) |
| 63 | { |
| 64 | int i; |
| 65 | u64 bytes = 0, packets = 0; |
| 66 | |
| 67 | for_each_possible_cpu(i) { |
| 68 | const struct pcpu_lstats *nl_stats; |
| 69 | u64 tbytes, tpackets; |
| 70 | unsigned int start; |
| 71 | |
| 72 | nl_stats = per_cpu_ptr(dev->lstats, i); |
| 73 | |
| 74 | do { |
Eric W. Biederman | 57a7744 | 2014-03-13 21:26:42 -0700 | [diff] [blame] | 75 | start = u64_stats_fetch_begin_irq(&nl_stats->syncp); |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 76 | tbytes = nl_stats->bytes; |
| 77 | tpackets = nl_stats->packets; |
Eric W. Biederman | 57a7744 | 2014-03-13 21:26:42 -0700 | [diff] [blame] | 78 | } while (u64_stats_fetch_retry_irq(&nl_stats->syncp, start)); |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 79 | |
| 80 | packets += tpackets; |
| 81 | bytes += tbytes; |
| 82 | } |
| 83 | |
| 84 | stats->rx_packets = packets; |
| 85 | stats->tx_packets = 0; |
| 86 | |
| 87 | stats->rx_bytes = bytes; |
| 88 | stats->tx_bytes = 0; |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 89 | } |
| 90 | |
| 91 | static u32 always_on(struct net_device *dev) |
| 92 | { |
| 93 | return 1; |
| 94 | } |
| 95 | |
| 96 | static const struct ethtool_ops nlmon_ethtool_ops = { |
| 97 | .get_link = always_on, |
| 98 | }; |
| 99 | |
| 100 | static const struct net_device_ops nlmon_ops = { |
| 101 | .ndo_init = nlmon_dev_init, |
| 102 | .ndo_uninit = nlmon_dev_uninit, |
| 103 | .ndo_open = nlmon_open, |
| 104 | .ndo_stop = nlmon_close, |
| 105 | .ndo_start_xmit = nlmon_xmit, |
| 106 | .ndo_get_stats64 = nlmon_get_stats64, |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 107 | }; |
| 108 | |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 109 | static void nlmon_setup(struct net_device *dev) |
| 110 | { |
| 111 | dev->type = ARPHRD_NETLINK; |
Phil Sutter | 85773a6 | 2015-08-18 10:30:33 +0200 | [diff] [blame] | 112 | dev->priv_flags |= IFF_NO_QUEUE; |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 113 | |
| 114 | dev->netdev_ops = &nlmon_ops; |
| 115 | dev->ethtool_ops = &nlmon_ethtool_ops; |
David S. Miller | cf124db | 2017-05-08 12:52:56 -0400 | [diff] [blame] | 116 | dev->needs_free_netdev = true; |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 117 | |
Daniel Borkmann | b7d47ca | 2014-03-27 16:34:59 +0100 | [diff] [blame] | 118 | dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | |
| 119 | NETIF_F_HIGHDMA | NETIF_F_LLTX; |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 120 | dev->flags = IFF_NOARP; |
| 121 | |
| 122 | /* That's rather a softlimit here, which, of course, |
| 123 | * can be altered. Not a real MTU, but what is to be |
| 124 | * expected in most cases. |
| 125 | */ |
| 126 | dev->mtu = NLMSG_GOODSIZE; |
Zhang Shengju | e82621e | 2016-12-07 17:26:05 +0800 | [diff] [blame] | 127 | dev->min_mtu = sizeof(struct nlmsghdr); |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 128 | } |
| 129 | |
Jiri Pirko | 7e6d4da | 2013-07-02 10:55:31 +0200 | [diff] [blame] | 130 | static int nlmon_validate(struct nlattr *tb[], struct nlattr *data[]) |
| 131 | { |
| 132 | if (tb[IFLA_ADDRESS]) |
| 133 | return -EINVAL; |
| 134 | return 0; |
| 135 | } |
| 136 | |
| 137 | static struct rtnl_link_ops nlmon_link_ops __read_mostly = { |
| 138 | .kind = "nlmon", |
| 139 | .priv_size = sizeof(struct nlmon), |
| 140 | .setup = nlmon_setup, |
| 141 | .validate = nlmon_validate, |
| 142 | }; |
| 143 | |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 144 | static __init int nlmon_register(void) |
| 145 | { |
Jiri Pirko | 7e6d4da | 2013-07-02 10:55:31 +0200 | [diff] [blame] | 146 | return rtnl_link_register(&nlmon_link_ops); |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 147 | } |
| 148 | |
| 149 | static __exit void nlmon_unregister(void) |
| 150 | { |
Jiri Pirko | 7e6d4da | 2013-07-02 10:55:31 +0200 | [diff] [blame] | 151 | rtnl_link_unregister(&nlmon_link_ops); |
Daniel Borkmann | e4fc408 | 2013-06-21 19:38:08 +0200 | [diff] [blame] | 152 | } |
| 153 | |
| 154 | module_init(nlmon_register); |
| 155 | module_exit(nlmon_unregister); |
| 156 | |
| 157 | MODULE_LICENSE("GPL v2"); |
| 158 | MODULE_AUTHOR("Daniel Borkmann <dborkman@redhat.com>"); |
| 159 | MODULE_AUTHOR("Mathieu Geli <geli@enseirb.fr>"); |
| 160 | MODULE_DESCRIPTION("Netlink monitoring device"); |
Jiri Pirko | 7e6d4da | 2013-07-02 10:55:31 +0200 | [diff] [blame] | 161 | MODULE_ALIAS_RTNL_LINK("nlmon"); |