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-rw-r--r--kernel/net/packet/af_packet.c4177
1 files changed, 4177 insertions, 0 deletions
diff --git a/kernel/net/packet/af_packet.c b/kernel/net/packet/af_packet.c
new file mode 100644
index 000000000..ef1eb2050
--- /dev/null
+++ b/kernel/net/packet/af_packet.c
@@ -0,0 +1,4177 @@
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * PACKET - implements raw packet sockets.
+ *
+ * Authors: Ross Biro
+ * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ * Alan Cox, <gw4pts@gw4pts.ampr.org>
+ *
+ * Fixes:
+ * Alan Cox : verify_area() now used correctly
+ * Alan Cox : new skbuff lists, look ma no backlogs!
+ * Alan Cox : tidied skbuff lists.
+ * Alan Cox : Now uses generic datagram routines I
+ * added. Also fixed the peek/read crash
+ * from all old Linux datagram code.
+ * Alan Cox : Uses the improved datagram code.
+ * Alan Cox : Added NULL's for socket options.
+ * Alan Cox : Re-commented the code.
+ * Alan Cox : Use new kernel side addressing
+ * Rob Janssen : Correct MTU usage.
+ * Dave Platt : Counter leaks caused by incorrect
+ * interrupt locking and some slightly
+ * dubious gcc output. Can you read
+ * compiler: it said _VOLATILE_
+ * Richard Kooijman : Timestamp fixes.
+ * Alan Cox : New buffers. Use sk->mac.raw.
+ * Alan Cox : sendmsg/recvmsg support.
+ * Alan Cox : Protocol setting support
+ * Alexey Kuznetsov : Untied from IPv4 stack.
+ * Cyrus Durgin : Fixed kerneld for kmod.
+ * Michal Ostrowski : Module initialization cleanup.
+ * Ulises Alonso : Frame number limit removal and
+ * packet_set_ring memory leak.
+ * Eric Biederman : Allow for > 8 byte hardware addresses.
+ * The convention is that longer addresses
+ * will simply extend the hardware address
+ * byte arrays at the end of sockaddr_ll
+ * and packet_mreq.
+ * Johann Baudy : Added TX RING.
+ * Chetan Loke : Implemented TPACKET_V3 block abstraction
+ * layer.
+ * Copyright (C) 2011, <lokec@ccs.neu.edu>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/capability.h>
+#include <linux/fcntl.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/if_packet.h>
+#include <linux/wireless.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/kmod.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <net/net_namespace.h>
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <linux/skbuff.h>
+#include <net/sock.h>
+#include <linux/errno.h>
+#include <linux/timer.h>
+#include <asm/uaccess.h>
+#include <asm/ioctls.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+#include <asm/io.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/poll.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/mutex.h>
+#include <linux/if_vlan.h>
+#include <linux/virtio_net.h>
+#include <linux/errqueue.h>
+#include <linux/net_tstamp.h>
+#include <linux/percpu.h>
+#ifdef CONFIG_INET
+#include <net/inet_common.h>
+#endif
+
+#include "internal.h"
+
+/*
+ Assumptions:
+ - if device has no dev->hard_header routine, it adds and removes ll header
+ inside itself. In this case ll header is invisible outside of device,
+ but higher levels still should reserve dev->hard_header_len.
+ Some devices are enough clever to reallocate skb, when header
+ will not fit to reserved space (tunnel), another ones are silly
+ (PPP).
+ - packet socket receives packets with pulled ll header,
+ so that SOCK_RAW should push it back.
+
+On receive:
+-----------
+
+Incoming, dev->hard_header!=NULL
+ mac_header -> ll header
+ data -> data
+
+Outgoing, dev->hard_header!=NULL
+ mac_header -> ll header
+ data -> ll header
+
+Incoming, dev->hard_header==NULL
+ mac_header -> UNKNOWN position. It is very likely, that it points to ll
+ header. PPP makes it, that is wrong, because introduce
+ assymetry between rx and tx paths.
+ data -> data
+
+Outgoing, dev->hard_header==NULL
+ mac_header -> data. ll header is still not built!
+ data -> data
+
+Resume
+ If dev->hard_header==NULL we are unlikely to restore sensible ll header.
+
+
+On transmit:
+------------
+
+dev->hard_header != NULL
+ mac_header -> ll header
+ data -> ll header
+
+dev->hard_header == NULL (ll header is added by device, we cannot control it)
+ mac_header -> data
+ data -> data
+
+ We should set nh.raw on output to correct posistion,
+ packet classifier depends on it.
+ */
+
+/* Private packet socket structures. */
+
+/* identical to struct packet_mreq except it has
+ * a longer address field.
+ */
+struct packet_mreq_max {
+ int mr_ifindex;
+ unsigned short mr_type;
+ unsigned short mr_alen;
+ unsigned char mr_address[MAX_ADDR_LEN];
+};
+
+union tpacket_uhdr {
+ struct tpacket_hdr *h1;
+ struct tpacket2_hdr *h2;
+ struct tpacket3_hdr *h3;
+ void *raw;
+};
+
+static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
+ int closing, int tx_ring);
+
+#define V3_ALIGNMENT (8)
+
+#define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
+
+#define BLK_PLUS_PRIV(sz_of_priv) \
+ (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
+
+#define PGV_FROM_VMALLOC 1
+
+#define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
+#define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
+#define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
+#define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
+#define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
+#define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
+#define BLOCK_PRIV(x) ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
+
+struct packet_sock;
+static int tpacket_snd(struct packet_sock *po, struct msghdr *msg);
+static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev);
+
+static void *packet_previous_frame(struct packet_sock *po,
+ struct packet_ring_buffer *rb,
+ int status);
+static void packet_increment_head(struct packet_ring_buffer *buff);
+static int prb_curr_blk_in_use(struct tpacket_kbdq_core *,
+ struct tpacket_block_desc *);
+static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
+ struct packet_sock *);
+static void prb_retire_current_block(struct tpacket_kbdq_core *,
+ struct packet_sock *, unsigned int status);
+static int prb_queue_frozen(struct tpacket_kbdq_core *);
+static void prb_open_block(struct tpacket_kbdq_core *,
+ struct tpacket_block_desc *);
+static void prb_retire_rx_blk_timer_expired(unsigned long);
+static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
+static void prb_init_blk_timer(struct packet_sock *,
+ struct tpacket_kbdq_core *,
+ void (*func) (unsigned long));
+static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
+static void prb_clear_rxhash(struct tpacket_kbdq_core *,
+ struct tpacket3_hdr *);
+static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
+ struct tpacket3_hdr *);
+static void packet_flush_mclist(struct sock *sk);
+
+struct packet_skb_cb {
+ union {
+ struct sockaddr_pkt pkt;
+ union {
+ /* Trick: alias skb original length with
+ * ll.sll_family and ll.protocol in order
+ * to save room.
+ */
+ unsigned int origlen;
+ struct sockaddr_ll ll;
+ };
+ } sa;
+};
+
+#define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
+
+#define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
+#define GET_PBLOCK_DESC(x, bid) \
+ ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
+#define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
+ ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
+#define GET_NEXT_PRB_BLK_NUM(x) \
+ (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
+ ((x)->kactive_blk_num+1) : 0)
+
+static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
+static void __fanout_link(struct sock *sk, struct packet_sock *po);
+
+static int packet_direct_xmit(struct sk_buff *skb)
+{
+ struct net_device *dev = skb->dev;
+ netdev_features_t features;
+ struct netdev_queue *txq;
+ int ret = NETDEV_TX_BUSY;
+
+ if (unlikely(!netif_running(dev) ||
+ !netif_carrier_ok(dev)))
+ goto drop;
+
+ features = netif_skb_features(skb);
+ if (skb_needs_linearize(skb, features) &&
+ __skb_linearize(skb))
+ goto drop;
+
+ txq = skb_get_tx_queue(dev, skb);
+
+ local_bh_disable();
+
+ HARD_TX_LOCK(dev, txq, smp_processor_id());
+ if (!netif_xmit_frozen_or_drv_stopped(txq))
+ ret = netdev_start_xmit(skb, dev, txq, false);
+ HARD_TX_UNLOCK(dev, txq);
+
+ local_bh_enable();
+
+ if (!dev_xmit_complete(ret))
+ kfree_skb(skb);
+
+ return ret;
+drop:
+ atomic_long_inc(&dev->tx_dropped);
+ kfree_skb(skb);
+ return NET_XMIT_DROP;
+}
+
+static struct net_device *packet_cached_dev_get(struct packet_sock *po)
+{
+ struct net_device *dev;
+
+ rcu_read_lock();
+ dev = rcu_dereference(po->cached_dev);
+ if (likely(dev))
+ dev_hold(dev);
+ rcu_read_unlock();
+
+ return dev;
+}
+
+static void packet_cached_dev_assign(struct packet_sock *po,
+ struct net_device *dev)
+{
+ rcu_assign_pointer(po->cached_dev, dev);
+}
+
+static void packet_cached_dev_reset(struct packet_sock *po)
+{
+ RCU_INIT_POINTER(po->cached_dev, NULL);
+}
+
+static bool packet_use_direct_xmit(const struct packet_sock *po)
+{
+ return po->xmit == packet_direct_xmit;
+}
+
+static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
+{
+ return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
+}
+
+static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
+{
+ const struct net_device_ops *ops = dev->netdev_ops;
+ u16 queue_index;
+
+ if (ops->ndo_select_queue) {
+ queue_index = ops->ndo_select_queue(dev, skb, NULL,
+ __packet_pick_tx_queue);
+ queue_index = netdev_cap_txqueue(dev, queue_index);
+ } else {
+ queue_index = __packet_pick_tx_queue(dev, skb);
+ }
+
+ skb_set_queue_mapping(skb, queue_index);
+}
+
+/* register_prot_hook must be invoked with the po->bind_lock held,
+ * or from a context in which asynchronous accesses to the packet
+ * socket is not possible (packet_create()).
+ */
+static void register_prot_hook(struct sock *sk)
+{
+ struct packet_sock *po = pkt_sk(sk);
+
+ if (!po->running) {
+ if (po->fanout)
+ __fanout_link(sk, po);
+ else
+ dev_add_pack(&po->prot_hook);
+
+ sock_hold(sk);
+ po->running = 1;
+ }
+}
+
+/* {,__}unregister_prot_hook() must be invoked with the po->bind_lock
+ * held. If the sync parameter is true, we will temporarily drop
+ * the po->bind_lock and do a synchronize_net to make sure no
+ * asynchronous packet processing paths still refer to the elements
+ * of po->prot_hook. If the sync parameter is false, it is the
+ * callers responsibility to take care of this.
+ */
+static void __unregister_prot_hook(struct sock *sk, bool sync)
+{
+ struct packet_sock *po = pkt_sk(sk);
+
+ po->running = 0;
+
+ if (po->fanout)
+ __fanout_unlink(sk, po);
+ else
+ __dev_remove_pack(&po->prot_hook);
+
+ __sock_put(sk);
+
+ if (sync) {
+ spin_unlock(&po->bind_lock);
+ synchronize_net();
+ spin_lock(&po->bind_lock);
+ }
+}
+
+static void unregister_prot_hook(struct sock *sk, bool sync)
+{
+ struct packet_sock *po = pkt_sk(sk);
+
+ if (po->running)
+ __unregister_prot_hook(sk, sync);
+}
+
+static inline struct page * __pure pgv_to_page(void *addr)
+{
+ if (is_vmalloc_addr(addr))
+ return vmalloc_to_page(addr);
+ return virt_to_page(addr);
+}
+
+static void __packet_set_status(struct packet_sock *po, void *frame, int status)
+{
+ union tpacket_uhdr h;
+
+ h.raw = frame;
+ switch (po->tp_version) {
+ case TPACKET_V1:
+ h.h1->tp_status = status;
+ flush_dcache_page(pgv_to_page(&h.h1->tp_status));
+ break;
+ case TPACKET_V2:
+ h.h2->tp_status = status;
+ flush_dcache_page(pgv_to_page(&h.h2->tp_status));
+ break;
+ case TPACKET_V3:
+ default:
+ WARN(1, "TPACKET version not supported.\n");
+ BUG();
+ }
+
+ smp_wmb();
+}
+
+static int __packet_get_status(struct packet_sock *po, void *frame)
+{
+ union tpacket_uhdr h;
+
+ smp_rmb();
+
+ h.raw = frame;
+ switch (po->tp_version) {
+ case TPACKET_V1:
+ flush_dcache_page(pgv_to_page(&h.h1->tp_status));
+ return h.h1->tp_status;
+ case TPACKET_V2:
+ flush_dcache_page(pgv_to_page(&h.h2->tp_status));
+ return h.h2->tp_status;
+ case TPACKET_V3:
+ default:
+ WARN(1, "TPACKET version not supported.\n");
+ BUG();
+ return 0;
+ }
+}
+
+static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
+ unsigned int flags)
+{
+ struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
+
+ if (shhwtstamps &&
+ (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
+ ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
+ return TP_STATUS_TS_RAW_HARDWARE;
+
+ if (ktime_to_timespec_cond(skb->tstamp, ts))
+ return TP_STATUS_TS_SOFTWARE;
+
+ return 0;
+}
+
+static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
+ struct sk_buff *skb)
+{
+ union tpacket_uhdr h;
+ struct timespec ts;
+ __u32 ts_status;
+
+ if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
+ return 0;
+
+ h.raw = frame;
+ switch (po->tp_version) {
+ case TPACKET_V1:
+ h.h1->tp_sec = ts.tv_sec;
+ h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
+ break;
+ case TPACKET_V2:
+ h.h2->tp_sec = ts.tv_sec;
+ h.h2->tp_nsec = ts.tv_nsec;
+ break;
+ case TPACKET_V3:
+ default:
+ WARN(1, "TPACKET version not supported.\n");
+ BUG();
+ }
+
+ /* one flush is safe, as both fields always lie on the same cacheline */
+ flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
+ smp_wmb();
+
+ return ts_status;
+}
+
+static void *packet_lookup_frame(struct packet_sock *po,
+ struct packet_ring_buffer *rb,
+ unsigned int position,
+ int status)
+{
+ unsigned int pg_vec_pos, frame_offset;
+ union tpacket_uhdr h;
+
+ pg_vec_pos = position / rb->frames_per_block;
+ frame_offset = position % rb->frames_per_block;
+
+ h.raw = rb->pg_vec[pg_vec_pos].buffer +
+ (frame_offset * rb->frame_size);
+
+ if (status != __packet_get_status(po, h.raw))
+ return NULL;
+
+ return h.raw;
+}
+
+static void *packet_current_frame(struct packet_sock *po,
+ struct packet_ring_buffer *rb,
+ int status)
+{
+ return packet_lookup_frame(po, rb, rb->head, status);
+}
+
+static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
+{
+ del_timer_sync(&pkc->retire_blk_timer);
+}
+
+static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
+ int tx_ring,
+ struct sk_buff_head *rb_queue)
+{
+ struct tpacket_kbdq_core *pkc;
+
+ pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
+ GET_PBDQC_FROM_RB(&po->rx_ring);
+
+ spin_lock_bh(&rb_queue->lock);
+ pkc->delete_blk_timer = 1;
+ spin_unlock_bh(&rb_queue->lock);
+
+ prb_del_retire_blk_timer(pkc);
+}
+
+static void prb_init_blk_timer(struct packet_sock *po,
+ struct tpacket_kbdq_core *pkc,
+ void (*func) (unsigned long))
+{
+ init_timer(&pkc->retire_blk_timer);
+ pkc->retire_blk_timer.data = (long)po;
+ pkc->retire_blk_timer.function = func;
+ pkc->retire_blk_timer.expires = jiffies;
+}
+
+static void prb_setup_retire_blk_timer(struct packet_sock *po, int tx_ring)
+{
+ struct tpacket_kbdq_core *pkc;
+
+ if (tx_ring)
+ BUG();
+
+ pkc = tx_ring ? GET_PBDQC_FROM_RB(&po->tx_ring) :
+ GET_PBDQC_FROM_RB(&po->rx_ring);
+ prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
+}
+
+static int prb_calc_retire_blk_tmo(struct packet_sock *po,
+ int blk_size_in_bytes)
+{
+ struct net_device *dev;
+ unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
+ struct ethtool_cmd ecmd;
+ int err;
+ u32 speed;
+
+ rtnl_lock();
+ dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
+ if (unlikely(!dev)) {
+ rtnl_unlock();
+ return DEFAULT_PRB_RETIRE_TOV;
+ }
+ err = __ethtool_get_settings(dev, &ecmd);
+ speed = ethtool_cmd_speed(&ecmd);
+ rtnl_unlock();
+ if (!err) {
+ /*
+ * If the link speed is so slow you don't really
+ * need to worry about perf anyways
+ */
+ if (speed < SPEED_1000 || speed == SPEED_UNKNOWN) {
+ return DEFAULT_PRB_RETIRE_TOV;
+ } else {
+ msec = 1;
+ div = speed / 1000;
+ }
+ }
+
+ mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
+
+ if (div)
+ mbits /= div;
+
+ tmo = mbits * msec;
+
+ if (div)
+ return tmo+1;
+ return tmo;
+}
+
+static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
+ union tpacket_req_u *req_u)
+{
+ p1->feature_req_word = req_u->req3.tp_feature_req_word;
+}
+
+static void init_prb_bdqc(struct packet_sock *po,
+ struct packet_ring_buffer *rb,
+ struct pgv *pg_vec,
+ union tpacket_req_u *req_u, int tx_ring)
+{
+ struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
+ struct tpacket_block_desc *pbd;
+
+ memset(p1, 0x0, sizeof(*p1));
+
+ p1->knxt_seq_num = 1;
+ p1->pkbdq = pg_vec;
+ pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
+ p1->pkblk_start = pg_vec[0].buffer;
+ p1->kblk_size = req_u->req3.tp_block_size;
+ p1->knum_blocks = req_u->req3.tp_block_nr;
+ p1->hdrlen = po->tp_hdrlen;
+ p1->version = po->tp_version;
+ p1->last_kactive_blk_num = 0;
+ po->stats.stats3.tp_freeze_q_cnt = 0;
+ if (req_u->req3.tp_retire_blk_tov)
+ p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
+ else
+ p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
+ req_u->req3.tp_block_size);
+ p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
+ p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
+
+ p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
+ prb_init_ft_ops(p1, req_u);
+ prb_setup_retire_blk_timer(po, tx_ring);
+ prb_open_block(p1, pbd);
+}
+
+/* Do NOT update the last_blk_num first.
+ * Assumes sk_buff_head lock is held.
+ */
+static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
+{
+ mod_timer(&pkc->retire_blk_timer,
+ jiffies + pkc->tov_in_jiffies);
+ pkc->last_kactive_blk_num = pkc->kactive_blk_num;
+}
+
+/*
+ * Timer logic:
+ * 1) We refresh the timer only when we open a block.
+ * By doing this we don't waste cycles refreshing the timer
+ * on packet-by-packet basis.
+ *
+ * With a 1MB block-size, on a 1Gbps line, it will take
+ * i) ~8 ms to fill a block + ii) memcpy etc.
+ * In this cut we are not accounting for the memcpy time.
+ *
+ * So, if the user sets the 'tmo' to 10ms then the timer
+ * will never fire while the block is still getting filled
+ * (which is what we want). However, the user could choose
+ * to close a block early and that's fine.
+ *
+ * But when the timer does fire, we check whether or not to refresh it.
+ * Since the tmo granularity is in msecs, it is not too expensive
+ * to refresh the timer, lets say every '8' msecs.
+ * Either the user can set the 'tmo' or we can derive it based on
+ * a) line-speed and b) block-size.
+ * prb_calc_retire_blk_tmo() calculates the tmo.
+ *
+ */
+static void prb_retire_rx_blk_timer_expired(unsigned long data)
+{
+ struct packet_sock *po = (struct packet_sock *)data;
+ struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
+ unsigned int frozen;
+ struct tpacket_block_desc *pbd;
+
+ spin_lock(&po->sk.sk_receive_queue.lock);
+
+ frozen = prb_queue_frozen(pkc);
+ pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
+
+ if (unlikely(pkc->delete_blk_timer))
+ goto out;
+
+ /* We only need to plug the race when the block is partially filled.
+ * tpacket_rcv:
+ * lock(); increment BLOCK_NUM_PKTS; unlock()
+ * copy_bits() is in progress ...
+ * timer fires on other cpu:
+ * we can't retire the current block because copy_bits
+ * is in progress.
+ *
+ */
+ if (BLOCK_NUM_PKTS(pbd)) {
+ while (atomic_read(&pkc->blk_fill_in_prog)) {
+ /* Waiting for skb_copy_bits to finish... */
+ cpu_chill();
+ }
+ }
+
+ if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
+ if (!frozen) {
+ if (!BLOCK_NUM_PKTS(pbd)) {
+ /* An empty block. Just refresh the timer. */
+ goto refresh_timer;
+ }
+ prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
+ if (!prb_dispatch_next_block(pkc, po))
+ goto refresh_timer;
+ else
+ goto out;
+ } else {
+ /* Case 1. Queue was frozen because user-space was
+ * lagging behind.
+ */
+ if (prb_curr_blk_in_use(pkc, pbd)) {
+ /*
+ * Ok, user-space is still behind.
+ * So just refresh the timer.
+ */
+ goto refresh_timer;
+ } else {
+ /* Case 2. queue was frozen,user-space caught up,
+ * now the link went idle && the timer fired.
+ * We don't have a block to close.So we open this
+ * block and restart the timer.
+ * opening a block thaws the queue,restarts timer
+ * Thawing/timer-refresh is a side effect.
+ */
+ prb_open_block(pkc, pbd);
+ goto out;
+ }
+ }
+ }
+
+refresh_timer:
+ _prb_refresh_rx_retire_blk_timer(pkc);
+
+out:
+ spin_unlock(&po->sk.sk_receive_queue.lock);
+}
+
+static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
+ struct tpacket_block_desc *pbd1, __u32 status)
+{
+ /* Flush everything minus the block header */
+
+#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
+ u8 *start, *end;
+
+ start = (u8 *)pbd1;
+
+ /* Skip the block header(we know header WILL fit in 4K) */
+ start += PAGE_SIZE;
+
+ end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
+ for (; start < end; start += PAGE_SIZE)
+ flush_dcache_page(pgv_to_page(start));
+
+ smp_wmb();
+#endif
+
+ /* Now update the block status. */
+
+ BLOCK_STATUS(pbd1) = status;
+
+ /* Flush the block header */
+
+#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
+ start = (u8 *)pbd1;
+ flush_dcache_page(pgv_to_page(start));
+
+ smp_wmb();
+#endif
+}
+
+/*
+ * Side effect:
+ *
+ * 1) flush the block
+ * 2) Increment active_blk_num
+ *
+ * Note:We DONT refresh the timer on purpose.
+ * Because almost always the next block will be opened.
+ */
+static void prb_close_block(struct tpacket_kbdq_core *pkc1,
+ struct tpacket_block_desc *pbd1,
+ struct packet_sock *po, unsigned int stat)
+{
+ __u32 status = TP_STATUS_USER | stat;
+
+ struct tpacket3_hdr *last_pkt;
+ struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
+ struct sock *sk = &po->sk;
+
+ if (po->stats.stats3.tp_drops)
+ status |= TP_STATUS_LOSING;
+
+ last_pkt = (struct tpacket3_hdr *)pkc1->prev;
+ last_pkt->tp_next_offset = 0;
+
+ /* Get the ts of the last pkt */
+ if (BLOCK_NUM_PKTS(pbd1)) {
+ h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
+ h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
+ } else {
+ /* Ok, we tmo'd - so get the current time.
+ *
+ * It shouldn't really happen as we don't close empty
+ * blocks. See prb_retire_rx_blk_timer_expired().
+ */
+ struct timespec ts;
+ getnstimeofday(&ts);
+ h1->ts_last_pkt.ts_sec = ts.tv_sec;
+ h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
+ }
+
+ smp_wmb();
+
+ /* Flush the block */
+ prb_flush_block(pkc1, pbd1, status);
+
+ sk->sk_data_ready(sk);
+
+ pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
+}
+
+static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
+{
+ pkc->reset_pending_on_curr_blk = 0;
+}
+
+/*
+ * Side effect of opening a block:
+ *
+ * 1) prb_queue is thawed.
+ * 2) retire_blk_timer is refreshed.
+ *
+ */
+static void prb_open_block(struct tpacket_kbdq_core *pkc1,
+ struct tpacket_block_desc *pbd1)
+{
+ struct timespec ts;
+ struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
+
+ smp_rmb();
+
+ /* We could have just memset this but we will lose the
+ * flexibility of making the priv area sticky
+ */
+
+ BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
+ BLOCK_NUM_PKTS(pbd1) = 0;
+ BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
+
+ getnstimeofday(&ts);
+
+ h1->ts_first_pkt.ts_sec = ts.tv_sec;
+ h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
+
+ pkc1->pkblk_start = (char *)pbd1;
+ pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
+
+ BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
+ BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
+
+ pbd1->version = pkc1->version;
+ pkc1->prev = pkc1->nxt_offset;
+ pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
+
+ prb_thaw_queue(pkc1);
+ _prb_refresh_rx_retire_blk_timer(pkc1);
+
+ smp_wmb();
+}
+
+/*
+ * Queue freeze logic:
+ * 1) Assume tp_block_nr = 8 blocks.
+ * 2) At time 't0', user opens Rx ring.
+ * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
+ * 4) user-space is either sleeping or processing block '0'.
+ * 5) tpacket_rcv is currently filling block '7', since there is no space left,
+ * it will close block-7,loop around and try to fill block '0'.
+ * call-flow:
+ * __packet_lookup_frame_in_block
+ * prb_retire_current_block()
+ * prb_dispatch_next_block()
+ * |->(BLOCK_STATUS == USER) evaluates to true
+ * 5.1) Since block-0 is currently in-use, we just freeze the queue.
+ * 6) Now there are two cases:
+ * 6.1) Link goes idle right after the queue is frozen.
+ * But remember, the last open_block() refreshed the timer.
+ * When this timer expires,it will refresh itself so that we can
+ * re-open block-0 in near future.
+ * 6.2) Link is busy and keeps on receiving packets. This is a simple
+ * case and __packet_lookup_frame_in_block will check if block-0
+ * is free and can now be re-used.
+ */
+static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
+ struct packet_sock *po)
+{
+ pkc->reset_pending_on_curr_blk = 1;
+ po->stats.stats3.tp_freeze_q_cnt++;
+}
+
+#define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
+
+/*
+ * If the next block is free then we will dispatch it
+ * and return a good offset.
+ * Else, we will freeze the queue.
+ * So, caller must check the return value.
+ */
+static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
+ struct packet_sock *po)
+{
+ struct tpacket_block_desc *pbd;
+
+ smp_rmb();
+
+ /* 1. Get current block num */
+ pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
+
+ /* 2. If this block is currently in_use then freeze the queue */
+ if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
+ prb_freeze_queue(pkc, po);
+ return NULL;
+ }
+
+ /*
+ * 3.
+ * open this block and return the offset where the first packet
+ * needs to get stored.
+ */
+ prb_open_block(pkc, pbd);
+ return (void *)pkc->nxt_offset;
+}
+
+static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
+ struct packet_sock *po, unsigned int status)
+{
+ struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
+
+ /* retire/close the current block */
+ if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
+ /*
+ * Plug the case where copy_bits() is in progress on
+ * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
+ * have space to copy the pkt in the current block and
+ * called prb_retire_current_block()
+ *
+ * We don't need to worry about the TMO case because
+ * the timer-handler already handled this case.
+ */
+ if (!(status & TP_STATUS_BLK_TMO)) {
+ while (atomic_read(&pkc->blk_fill_in_prog)) {
+ /* Waiting for skb_copy_bits to finish... */
+ cpu_chill();
+ }
+ }
+ prb_close_block(pkc, pbd, po, status);
+ return;
+ }
+}
+
+static int prb_curr_blk_in_use(struct tpacket_kbdq_core *pkc,
+ struct tpacket_block_desc *pbd)
+{
+ return TP_STATUS_USER & BLOCK_STATUS(pbd);
+}
+
+static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
+{
+ return pkc->reset_pending_on_curr_blk;
+}
+
+static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
+{
+ struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
+ atomic_dec(&pkc->blk_fill_in_prog);
+}
+
+static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
+ struct tpacket3_hdr *ppd)
+{
+ ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
+}
+
+static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
+ struct tpacket3_hdr *ppd)
+{
+ ppd->hv1.tp_rxhash = 0;
+}
+
+static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
+ struct tpacket3_hdr *ppd)
+{
+ if (skb_vlan_tag_present(pkc->skb)) {
+ ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
+ ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
+ ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
+ } else {
+ ppd->hv1.tp_vlan_tci = 0;
+ ppd->hv1.tp_vlan_tpid = 0;
+ ppd->tp_status = TP_STATUS_AVAILABLE;
+ }
+}
+
+static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
+ struct tpacket3_hdr *ppd)
+{
+ ppd->hv1.tp_padding = 0;
+ prb_fill_vlan_info(pkc, ppd);
+
+ if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
+ prb_fill_rxhash(pkc, ppd);
+ else
+ prb_clear_rxhash(pkc, ppd);
+}
+
+static void prb_fill_curr_block(char *curr,
+ struct tpacket_kbdq_core *pkc,
+ struct tpacket_block_desc *pbd,
+ unsigned int len)
+{
+ struct tpacket3_hdr *ppd;
+
+ ppd = (struct tpacket3_hdr *)curr;
+ ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
+ pkc->prev = curr;
+ pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
+ BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
+ BLOCK_NUM_PKTS(pbd) += 1;
+ atomic_inc(&pkc->blk_fill_in_prog);
+ prb_run_all_ft_ops(pkc, ppd);
+}
+
+/* Assumes caller has the sk->rx_queue.lock */
+static void *__packet_lookup_frame_in_block(struct packet_sock *po,
+ struct sk_buff *skb,
+ int status,
+ unsigned int len
+ )
+{
+ struct tpacket_kbdq_core *pkc;
+ struct tpacket_block_desc *pbd;
+ char *curr, *end;
+
+ pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
+ pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
+
+ /* Queue is frozen when user space is lagging behind */
+ if (prb_queue_frozen(pkc)) {
+ /*
+ * Check if that last block which caused the queue to freeze,
+ * is still in_use by user-space.
+ */
+ if (prb_curr_blk_in_use(pkc, pbd)) {
+ /* Can't record this packet */
+ return NULL;
+ } else {
+ /*
+ * Ok, the block was released by user-space.
+ * Now let's open that block.
+ * opening a block also thaws the queue.
+ * Thawing is a side effect.
+ */
+ prb_open_block(pkc, pbd);
+ }
+ }
+
+ smp_mb();
+ curr = pkc->nxt_offset;
+ pkc->skb = skb;
+ end = (char *)pbd + pkc->kblk_size;
+
+ /* first try the current block */
+ if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
+ prb_fill_curr_block(curr, pkc, pbd, len);
+ return (void *)curr;
+ }
+
+ /* Ok, close the current block */
+ prb_retire_current_block(pkc, po, 0);
+
+ /* Now, try to dispatch the next block */
+ curr = (char *)prb_dispatch_next_block(pkc, po);
+ if (curr) {
+ pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
+ prb_fill_curr_block(curr, pkc, pbd, len);
+ return (void *)curr;
+ }
+
+ /*
+ * No free blocks are available.user_space hasn't caught up yet.
+ * Queue was just frozen and now this packet will get dropped.
+ */
+ return NULL;
+}
+
+static void *packet_current_rx_frame(struct packet_sock *po,
+ struct sk_buff *skb,
+ int status, unsigned int len)
+{
+ char *curr = NULL;
+ switch (po->tp_version) {
+ case TPACKET_V1:
+ case TPACKET_V2:
+ curr = packet_lookup_frame(po, &po->rx_ring,
+ po->rx_ring.head, status);
+ return curr;
+ case TPACKET_V3:
+ return __packet_lookup_frame_in_block(po, skb, status, len);
+ default:
+ WARN(1, "TPACKET version not supported\n");
+ BUG();
+ return NULL;
+ }
+}
+
+static void *prb_lookup_block(struct packet_sock *po,
+ struct packet_ring_buffer *rb,
+ unsigned int idx,
+ int status)
+{
+ struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
+ struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
+
+ if (status != BLOCK_STATUS(pbd))
+ return NULL;
+ return pbd;
+}
+
+static int prb_previous_blk_num(struct packet_ring_buffer *rb)
+{
+ unsigned int prev;
+ if (rb->prb_bdqc.kactive_blk_num)
+ prev = rb->prb_bdqc.kactive_blk_num-1;
+ else
+ prev = rb->prb_bdqc.knum_blocks-1;
+ return prev;
+}
+
+/* Assumes caller has held the rx_queue.lock */
+static void *__prb_previous_block(struct packet_sock *po,
+ struct packet_ring_buffer *rb,
+ int status)
+{
+ unsigned int previous = prb_previous_blk_num(rb);
+ return prb_lookup_block(po, rb, previous, status);
+}
+
+static void *packet_previous_rx_frame(struct packet_sock *po,
+ struct packet_ring_buffer *rb,
+ int status)
+{
+ if (po->tp_version <= TPACKET_V2)
+ return packet_previous_frame(po, rb, status);
+
+ return __prb_previous_block(po, rb, status);
+}
+
+static void packet_increment_rx_head(struct packet_sock *po,
+ struct packet_ring_buffer *rb)
+{
+ switch (po->tp_version) {
+ case TPACKET_V1:
+ case TPACKET_V2:
+ return packet_increment_head(rb);
+ case TPACKET_V3:
+ default:
+ WARN(1, "TPACKET version not supported.\n");
+ BUG();
+ return;
+ }
+}
+
+static void *packet_previous_frame(struct packet_sock *po,
+ struct packet_ring_buffer *rb,
+ int status)
+{
+ unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
+ return packet_lookup_frame(po, rb, previous, status);
+}
+
+static void packet_increment_head(struct packet_ring_buffer *buff)
+{
+ buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
+}
+
+static void packet_inc_pending(struct packet_ring_buffer *rb)
+{
+ this_cpu_inc(*rb->pending_refcnt);
+}
+
+static void packet_dec_pending(struct packet_ring_buffer *rb)
+{
+ this_cpu_dec(*rb->pending_refcnt);
+}
+
+static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
+{
+ unsigned int refcnt = 0;
+ int cpu;
+
+ /* We don't use pending refcount in rx_ring. */
+ if (rb->pending_refcnt == NULL)
+ return 0;
+
+ for_each_possible_cpu(cpu)
+ refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
+
+ return refcnt;
+}
+
+static int packet_alloc_pending(struct packet_sock *po)
+{
+ po->rx_ring.pending_refcnt = NULL;
+
+ po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
+ if (unlikely(po->tx_ring.pending_refcnt == NULL))
+ return -ENOBUFS;
+
+ return 0;
+}
+
+static void packet_free_pending(struct packet_sock *po)
+{
+ free_percpu(po->tx_ring.pending_refcnt);
+}
+
+static bool packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
+{
+ struct sock *sk = &po->sk;
+ bool has_room;
+
+ if (po->prot_hook.func != tpacket_rcv)
+ return (atomic_read(&sk->sk_rmem_alloc) + skb->truesize)
+ <= sk->sk_rcvbuf;
+
+ spin_lock(&sk->sk_receive_queue.lock);
+ if (po->tp_version == TPACKET_V3)
+ has_room = prb_lookup_block(po, &po->rx_ring,
+ po->rx_ring.prb_bdqc.kactive_blk_num,
+ TP_STATUS_KERNEL);
+ else
+ has_room = packet_lookup_frame(po, &po->rx_ring,
+ po->rx_ring.head,
+ TP_STATUS_KERNEL);
+ spin_unlock(&sk->sk_receive_queue.lock);
+
+ return has_room;
+}
+
+static void packet_sock_destruct(struct sock *sk)
+{
+ skb_queue_purge(&sk->sk_error_queue);
+
+ WARN_ON(atomic_read(&sk->sk_rmem_alloc));
+ WARN_ON(atomic_read(&sk->sk_wmem_alloc));
+
+ if (!sock_flag(sk, SOCK_DEAD)) {
+ pr_err("Attempt to release alive packet socket: %p\n", sk);
+ return;
+ }
+
+ sk_refcnt_debug_dec(sk);
+}
+
+static unsigned int fanout_demux_hash(struct packet_fanout *f,
+ struct sk_buff *skb,
+ unsigned int num)
+{
+ return reciprocal_scale(skb_get_hash(skb), num);
+}
+
+static unsigned int fanout_demux_lb(struct packet_fanout *f,
+ struct sk_buff *skb,
+ unsigned int num)
+{
+ unsigned int val = atomic_inc_return(&f->rr_cur);
+
+ return val % num;
+}
+
+static unsigned int fanout_demux_cpu(struct packet_fanout *f,
+ struct sk_buff *skb,
+ unsigned int num)
+{
+ return smp_processor_id() % num;
+}
+
+static unsigned int fanout_demux_rnd(struct packet_fanout *f,
+ struct sk_buff *skb,
+ unsigned int num)
+{
+ return prandom_u32_max(num);
+}
+
+static unsigned int fanout_demux_rollover(struct packet_fanout *f,
+ struct sk_buff *skb,
+ unsigned int idx, unsigned int skip,
+ unsigned int num)
+{
+ unsigned int i, j;
+
+ i = j = min_t(int, f->next[idx], num - 1);
+ do {
+ if (i != skip && packet_rcv_has_room(pkt_sk(f->arr[i]), skb)) {
+ if (i != j)
+ f->next[idx] = i;
+ return i;
+ }
+ if (++i == num)
+ i = 0;
+ } while (i != j);
+
+ return idx;
+}
+
+static unsigned int fanout_demux_qm(struct packet_fanout *f,
+ struct sk_buff *skb,
+ unsigned int num)
+{
+ return skb_get_queue_mapping(skb) % num;
+}
+
+static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
+{
+ return f->flags & (flag >> 8);
+}
+
+static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct packet_fanout *f = pt->af_packet_priv;
+ unsigned int num = READ_ONCE(f->num_members);
+ struct packet_sock *po;
+ unsigned int idx;
+
+ if (!net_eq(dev_net(dev), read_pnet(&f->net)) ||
+ !num) {
+ kfree_skb(skb);
+ return 0;
+ }
+
+ if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
+ skb = ip_check_defrag(skb, IP_DEFRAG_AF_PACKET);
+ if (!skb)
+ return 0;
+ }
+ switch (f->type) {
+ case PACKET_FANOUT_HASH:
+ default:
+ idx = fanout_demux_hash(f, skb, num);
+ break;
+ case PACKET_FANOUT_LB:
+ idx = fanout_demux_lb(f, skb, num);
+ break;
+ case PACKET_FANOUT_CPU:
+ idx = fanout_demux_cpu(f, skb, num);
+ break;
+ case PACKET_FANOUT_RND:
+ idx = fanout_demux_rnd(f, skb, num);
+ break;
+ case PACKET_FANOUT_QM:
+ idx = fanout_demux_qm(f, skb, num);
+ break;
+ case PACKET_FANOUT_ROLLOVER:
+ idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
+ break;
+ }
+
+ po = pkt_sk(f->arr[idx]);
+ if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER) &&
+ unlikely(!packet_rcv_has_room(po, skb))) {
+ idx = fanout_demux_rollover(f, skb, idx, idx, num);
+ po = pkt_sk(f->arr[idx]);
+ }
+
+ return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
+}
+
+DEFINE_MUTEX(fanout_mutex);
+EXPORT_SYMBOL_GPL(fanout_mutex);
+static LIST_HEAD(fanout_list);
+
+static void __fanout_link(struct sock *sk, struct packet_sock *po)
+{
+ struct packet_fanout *f = po->fanout;
+
+ spin_lock(&f->lock);
+ f->arr[f->num_members] = sk;
+ smp_wmb();
+ f->num_members++;
+ spin_unlock(&f->lock);
+}
+
+static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
+{
+ struct packet_fanout *f = po->fanout;
+ int i;
+
+ spin_lock(&f->lock);
+ for (i = 0; i < f->num_members; i++) {
+ if (f->arr[i] == sk)
+ break;
+ }
+ BUG_ON(i >= f->num_members);
+ f->arr[i] = f->arr[f->num_members - 1];
+ f->num_members--;
+ spin_unlock(&f->lock);
+}
+
+static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
+{
+ if (ptype->af_packet_priv == (void *)((struct packet_sock *)sk)->fanout)
+ return true;
+
+ return false;
+}
+
+static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
+{
+ struct packet_sock *po = pkt_sk(sk);
+ struct packet_fanout *f, *match;
+ u8 type = type_flags & 0xff;
+ u8 flags = type_flags >> 8;
+ int err;
+
+ switch (type) {
+ case PACKET_FANOUT_ROLLOVER:
+ if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
+ return -EINVAL;
+ case PACKET_FANOUT_HASH:
+ case PACKET_FANOUT_LB:
+ case PACKET_FANOUT_CPU:
+ case PACKET_FANOUT_RND:
+ case PACKET_FANOUT_QM:
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ if (!po->running)
+ return -EINVAL;
+
+ if (po->fanout)
+ return -EALREADY;
+
+ mutex_lock(&fanout_mutex);
+ match = NULL;
+ list_for_each_entry(f, &fanout_list, list) {
+ if (f->id == id &&
+ read_pnet(&f->net) == sock_net(sk)) {
+ match = f;
+ break;
+ }
+ }
+ err = -EINVAL;
+ if (match && match->flags != flags)
+ goto out;
+ if (!match) {
+ err = -ENOMEM;
+ match = kzalloc(sizeof(*match), GFP_KERNEL);
+ if (!match)
+ goto out;
+ write_pnet(&match->net, sock_net(sk));
+ match->id = id;
+ match->type = type;
+ match->flags = flags;
+ atomic_set(&match->rr_cur, 0);
+ INIT_LIST_HEAD(&match->list);
+ spin_lock_init(&match->lock);
+ atomic_set(&match->sk_ref, 0);
+ match->prot_hook.type = po->prot_hook.type;
+ match->prot_hook.dev = po->prot_hook.dev;
+ match->prot_hook.func = packet_rcv_fanout;
+ match->prot_hook.af_packet_priv = match;
+ match->prot_hook.id_match = match_fanout_group;
+ dev_add_pack(&match->prot_hook);
+ list_add(&match->list, &fanout_list);
+ }
+ err = -EINVAL;
+ if (match->type == type &&
+ match->prot_hook.type == po->prot_hook.type &&
+ match->prot_hook.dev == po->prot_hook.dev) {
+ err = -ENOSPC;
+ if (atomic_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
+ __dev_remove_pack(&po->prot_hook);
+ po->fanout = match;
+ atomic_inc(&match->sk_ref);
+ __fanout_link(sk, po);
+ err = 0;
+ }
+ }
+out:
+ mutex_unlock(&fanout_mutex);
+ return err;
+}
+
+static void fanout_release(struct sock *sk)
+{
+ struct packet_sock *po = pkt_sk(sk);
+ struct packet_fanout *f;
+
+ f = po->fanout;
+ if (!f)
+ return;
+
+ mutex_lock(&fanout_mutex);
+ po->fanout = NULL;
+
+ if (atomic_dec_and_test(&f->sk_ref)) {
+ list_del(&f->list);
+ dev_remove_pack(&f->prot_hook);
+ kfree(f);
+ }
+ mutex_unlock(&fanout_mutex);
+}
+
+static const struct proto_ops packet_ops;
+
+static const struct proto_ops packet_ops_spkt;
+
+static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct sock *sk;
+ struct sockaddr_pkt *spkt;
+
+ /*
+ * When we registered the protocol we saved the socket in the data
+ * field for just this event.
+ */
+
+ sk = pt->af_packet_priv;
+
+ /*
+ * Yank back the headers [hope the device set this
+ * right or kerboom...]
+ *
+ * Incoming packets have ll header pulled,
+ * push it back.
+ *
+ * For outgoing ones skb->data == skb_mac_header(skb)
+ * so that this procedure is noop.
+ */
+
+ if (skb->pkt_type == PACKET_LOOPBACK)
+ goto out;
+
+ if (!net_eq(dev_net(dev), sock_net(sk)))
+ goto out;
+
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ if (skb == NULL)
+ goto oom;
+
+ /* drop any routing info */
+ skb_dst_drop(skb);
+
+ /* drop conntrack reference */
+ nf_reset(skb);
+
+ spkt = &PACKET_SKB_CB(skb)->sa.pkt;
+
+ skb_push(skb, skb->data - skb_mac_header(skb));
+
+ /*
+ * The SOCK_PACKET socket receives _all_ frames.
+ */
+
+ spkt->spkt_family = dev->type;
+ strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
+ spkt->spkt_protocol = skb->protocol;
+
+ /*
+ * Charge the memory to the socket. This is done specifically
+ * to prevent sockets using all the memory up.
+ */
+
+ if (sock_queue_rcv_skb(sk, skb) == 0)
+ return 0;
+
+out:
+ kfree_skb(skb);
+oom:
+ return 0;
+}
+
+
+/*
+ * Output a raw packet to a device layer. This bypasses all the other
+ * protocol layers and you must therefore supply it with a complete frame
+ */
+
+static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
+ size_t len)
+{
+ struct sock *sk = sock->sk;
+ DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
+ struct sk_buff *skb = NULL;
+ struct net_device *dev;
+ __be16 proto = 0;
+ int err;
+ int extra_len = 0;
+
+ /*
+ * Get and verify the address.
+ */
+
+ if (saddr) {
+ if (msg->msg_namelen < sizeof(struct sockaddr))
+ return -EINVAL;
+ if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
+ proto = saddr->spkt_protocol;
+ } else
+ return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
+
+ /*
+ * Find the device first to size check it
+ */
+
+ saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
+retry:
+ rcu_read_lock();
+ dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
+ err = -ENODEV;
+ if (dev == NULL)
+ goto out_unlock;
+
+ err = -ENETDOWN;
+ if (!(dev->flags & IFF_UP))
+ goto out_unlock;
+
+ /*
+ * You may not queue a frame bigger than the mtu. This is the lowest level
+ * raw protocol and you must do your own fragmentation at this level.
+ */
+
+ if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
+ if (!netif_supports_nofcs(dev)) {
+ err = -EPROTONOSUPPORT;
+ goto out_unlock;
+ }
+ extra_len = 4; /* We're doing our own CRC */
+ }
+
+ err = -EMSGSIZE;
+ if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
+ goto out_unlock;
+
+ if (!skb) {
+ size_t reserved = LL_RESERVED_SPACE(dev);
+ int tlen = dev->needed_tailroom;
+ unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
+
+ rcu_read_unlock();
+ skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
+ if (skb == NULL)
+ return -ENOBUFS;
+ /* FIXME: Save some space for broken drivers that write a hard
+ * header at transmission time by themselves. PPP is the notable
+ * one here. This should really be fixed at the driver level.
+ */
+ skb_reserve(skb, reserved);
+ skb_reset_network_header(skb);
+
+ /* Try to align data part correctly */
+ if (hhlen) {
+ skb->data -= hhlen;
+ skb->tail -= hhlen;
+ if (len < hhlen)
+ skb_reset_network_header(skb);
+ }
+ err = memcpy_from_msg(skb_put(skb, len), msg, len);
+ if (err)
+ goto out_free;
+ goto retry;
+ }
+
+ if (len > (dev->mtu + dev->hard_header_len + extra_len)) {
+ /* Earlier code assumed this would be a VLAN pkt,
+ * double-check this now that we have the actual
+ * packet in hand.
+ */
+ struct ethhdr *ehdr;
+ skb_reset_mac_header(skb);
+ ehdr = eth_hdr(skb);
+ if (ehdr->h_proto != htons(ETH_P_8021Q)) {
+ err = -EMSGSIZE;
+ goto out_unlock;
+ }
+ }
+
+ skb->protocol = proto;
+ skb->dev = dev;
+ skb->priority = sk->sk_priority;
+ skb->mark = sk->sk_mark;
+
+ sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
+
+ if (unlikely(extra_len == 4))
+ skb->no_fcs = 1;
+
+ skb_probe_transport_header(skb, 0);
+
+ dev_queue_xmit(skb);
+ rcu_read_unlock();
+ return len;
+
+out_unlock:
+ rcu_read_unlock();
+out_free:
+ kfree_skb(skb);
+ return err;
+}
+
+static unsigned int run_filter(const struct sk_buff *skb,
+ const struct sock *sk,
+ unsigned int res)
+{
+ struct sk_filter *filter;
+
+ rcu_read_lock();
+ filter = rcu_dereference(sk->sk_filter);
+ if (filter != NULL)
+ res = SK_RUN_FILTER(filter, skb);
+ rcu_read_unlock();
+
+ return res;
+}
+
+/*
+ * This function makes lazy skb cloning in hope that most of packets
+ * are discarded by BPF.
+ *
+ * Note tricky part: we DO mangle shared skb! skb->data, skb->len
+ * and skb->cb are mangled. It works because (and until) packets
+ * falling here are owned by current CPU. Output packets are cloned
+ * by dev_queue_xmit_nit(), input packets are processed by net_bh
+ * sequencially, so that if we return skb to original state on exit,
+ * we will not harm anyone.
+ */
+
+static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct sock *sk;
+ struct sockaddr_ll *sll;
+ struct packet_sock *po;
+ u8 *skb_head = skb->data;
+ int skb_len = skb->len;
+ unsigned int snaplen, res;
+
+ if (skb->pkt_type == PACKET_LOOPBACK)
+ goto drop;
+
+ sk = pt->af_packet_priv;
+ po = pkt_sk(sk);
+
+ if (!net_eq(dev_net(dev), sock_net(sk)))
+ goto drop;
+
+ skb->dev = dev;
+
+ if (dev->header_ops) {
+ /* The device has an explicit notion of ll header,
+ * exported to higher levels.
+ *
+ * Otherwise, the device hides details of its frame
+ * structure, so that corresponding packet head is
+ * never delivered to user.
+ */
+ if (sk->sk_type != SOCK_DGRAM)
+ skb_push(skb, skb->data - skb_mac_header(skb));
+ else if (skb->pkt_type == PACKET_OUTGOING) {
+ /* Special case: outgoing packets have ll header at head */
+ skb_pull(skb, skb_network_offset(skb));
+ }
+ }
+
+ snaplen = skb->len;
+
+ res = run_filter(skb, sk, snaplen);
+ if (!res)
+ goto drop_n_restore;
+ if (snaplen > res)
+ snaplen = res;
+
+ if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
+ goto drop_n_acct;
+
+ if (skb_shared(skb)) {
+ struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
+ if (nskb == NULL)
+ goto drop_n_acct;
+
+ if (skb_head != skb->data) {
+ skb->data = skb_head;
+ skb->len = skb_len;
+ }
+ consume_skb(skb);
+ skb = nskb;
+ }
+
+ sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
+
+ sll = &PACKET_SKB_CB(skb)->sa.ll;
+ sll->sll_hatype = dev->type;
+ sll->sll_pkttype = skb->pkt_type;
+ if (unlikely(po->origdev))
+ sll->sll_ifindex = orig_dev->ifindex;
+ else
+ sll->sll_ifindex = dev->ifindex;
+
+ sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
+
+ /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
+ * Use their space for storing the original skb length.
+ */
+ PACKET_SKB_CB(skb)->sa.origlen = skb->len;
+
+ if (pskb_trim(skb, snaplen))
+ goto drop_n_acct;
+
+ skb_set_owner_r(skb, sk);
+ skb->dev = NULL;
+ skb_dst_drop(skb);
+
+ /* drop conntrack reference */
+ nf_reset(skb);
+
+ spin_lock(&sk->sk_receive_queue.lock);
+ po->stats.stats1.tp_packets++;
+ sock_skb_set_dropcount(sk, skb);
+ __skb_queue_tail(&sk->sk_receive_queue, skb);
+ spin_unlock(&sk->sk_receive_queue.lock);
+ sk->sk_data_ready(sk);
+ return 0;
+
+drop_n_acct:
+ spin_lock(&sk->sk_receive_queue.lock);
+ po->stats.stats1.tp_drops++;
+ atomic_inc(&sk->sk_drops);
+ spin_unlock(&sk->sk_receive_queue.lock);
+
+drop_n_restore:
+ if (skb_head != skb->data && skb_shared(skb)) {
+ skb->data = skb_head;
+ skb->len = skb_len;
+ }
+drop:
+ consume_skb(skb);
+ return 0;
+}
+
+static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct sock *sk;
+ struct packet_sock *po;
+ struct sockaddr_ll *sll;
+ union tpacket_uhdr h;
+ u8 *skb_head = skb->data;
+ int skb_len = skb->len;
+ unsigned int snaplen, res;
+ unsigned long status = TP_STATUS_USER;
+ unsigned short macoff, netoff, hdrlen;
+ struct sk_buff *copy_skb = NULL;
+ struct timespec ts;
+ __u32 ts_status;
+
+ /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
+ * We may add members to them until current aligned size without forcing
+ * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
+ */
+ BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
+ BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
+
+ if (skb->pkt_type == PACKET_LOOPBACK)
+ goto drop;
+
+ sk = pt->af_packet_priv;
+ po = pkt_sk(sk);
+
+ if (!net_eq(dev_net(dev), sock_net(sk)))
+ goto drop;
+
+ if (dev->header_ops) {
+ if (sk->sk_type != SOCK_DGRAM)
+ skb_push(skb, skb->data - skb_mac_header(skb));
+ else if (skb->pkt_type == PACKET_OUTGOING) {
+ /* Special case: outgoing packets have ll header at head */
+ skb_pull(skb, skb_network_offset(skb));
+ }
+ }
+
+ snaplen = skb->len;
+
+ res = run_filter(skb, sk, snaplen);
+ if (!res)
+ goto drop_n_restore;
+
+ if (skb->ip_summed == CHECKSUM_PARTIAL)
+ status |= TP_STATUS_CSUMNOTREADY;
+ else if (skb->pkt_type != PACKET_OUTGOING &&
+ (skb->ip_summed == CHECKSUM_COMPLETE ||
+ skb_csum_unnecessary(skb)))
+ status |= TP_STATUS_CSUM_VALID;
+
+ if (snaplen > res)
+ snaplen = res;
+
+ if (sk->sk_type == SOCK_DGRAM) {
+ macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
+ po->tp_reserve;
+ } else {
+ unsigned int maclen = skb_network_offset(skb);
+ netoff = TPACKET_ALIGN(po->tp_hdrlen +
+ (maclen < 16 ? 16 : maclen)) +
+ po->tp_reserve;
+ macoff = netoff - maclen;
+ }
+ if (po->tp_version <= TPACKET_V2) {
+ if (macoff + snaplen > po->rx_ring.frame_size) {
+ if (po->copy_thresh &&
+ atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
+ if (skb_shared(skb)) {
+ copy_skb = skb_clone(skb, GFP_ATOMIC);
+ } else {
+ copy_skb = skb_get(skb);
+ skb_head = skb->data;
+ }
+ if (copy_skb)
+ skb_set_owner_r(copy_skb, sk);
+ }
+ snaplen = po->rx_ring.frame_size - macoff;
+ if ((int)snaplen < 0)
+ snaplen = 0;
+ }
+ } else if (unlikely(macoff + snaplen >
+ GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
+ u32 nval;
+
+ nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
+ pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
+ snaplen, nval, macoff);
+ snaplen = nval;
+ if (unlikely((int)snaplen < 0)) {
+ snaplen = 0;
+ macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
+ }
+ }
+ spin_lock(&sk->sk_receive_queue.lock);
+ h.raw = packet_current_rx_frame(po, skb,
+ TP_STATUS_KERNEL, (macoff+snaplen));
+ if (!h.raw)
+ goto ring_is_full;
+ if (po->tp_version <= TPACKET_V2) {
+ packet_increment_rx_head(po, &po->rx_ring);
+ /*
+ * LOSING will be reported till you read the stats,
+ * because it's COR - Clear On Read.
+ * Anyways, moving it for V1/V2 only as V3 doesn't need this
+ * at packet level.
+ */
+ if (po->stats.stats1.tp_drops)
+ status |= TP_STATUS_LOSING;
+ }
+ po->stats.stats1.tp_packets++;
+ if (copy_skb) {
+ status |= TP_STATUS_COPY;
+ __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
+ }
+ spin_unlock(&sk->sk_receive_queue.lock);
+
+ skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
+
+ if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
+ getnstimeofday(&ts);
+
+ status |= ts_status;
+
+ switch (po->tp_version) {
+ case TPACKET_V1:
+ h.h1->tp_len = skb->len;
+ h.h1->tp_snaplen = snaplen;
+ h.h1->tp_mac = macoff;
+ h.h1->tp_net = netoff;
+ h.h1->tp_sec = ts.tv_sec;
+ h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
+ hdrlen = sizeof(*h.h1);
+ break;
+ case TPACKET_V2:
+ h.h2->tp_len = skb->len;
+ h.h2->tp_snaplen = snaplen;
+ h.h2->tp_mac = macoff;
+ h.h2->tp_net = netoff;
+ h.h2->tp_sec = ts.tv_sec;
+ h.h2->tp_nsec = ts.tv_nsec;
+ if (skb_vlan_tag_present(skb)) {
+ h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
+ h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
+ status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
+ } else {
+ h.h2->tp_vlan_tci = 0;
+ h.h2->tp_vlan_tpid = 0;
+ }
+ memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
+ hdrlen = sizeof(*h.h2);
+ break;
+ case TPACKET_V3:
+ /* tp_nxt_offset,vlan are already populated above.
+ * So DONT clear those fields here
+ */
+ h.h3->tp_status |= status;
+ h.h3->tp_len = skb->len;
+ h.h3->tp_snaplen = snaplen;
+ h.h3->tp_mac = macoff;
+ h.h3->tp_net = netoff;
+ h.h3->tp_sec = ts.tv_sec;
+ h.h3->tp_nsec = ts.tv_nsec;
+ memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
+ hdrlen = sizeof(*h.h3);
+ break;
+ default:
+ BUG();
+ }
+
+ sll = h.raw + TPACKET_ALIGN(hdrlen);
+ sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
+ sll->sll_family = AF_PACKET;
+ sll->sll_hatype = dev->type;
+ sll->sll_protocol = skb->protocol;
+ sll->sll_pkttype = skb->pkt_type;
+ if (unlikely(po->origdev))
+ sll->sll_ifindex = orig_dev->ifindex;
+ else
+ sll->sll_ifindex = dev->ifindex;
+
+ smp_mb();
+
+#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
+ if (po->tp_version <= TPACKET_V2) {
+ u8 *start, *end;
+
+ end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
+ macoff + snaplen);
+
+ for (start = h.raw; start < end; start += PAGE_SIZE)
+ flush_dcache_page(pgv_to_page(start));
+ }
+ smp_wmb();
+#endif
+
+ if (po->tp_version <= TPACKET_V2) {
+ __packet_set_status(po, h.raw, status);
+ sk->sk_data_ready(sk);
+ } else {
+ prb_clear_blk_fill_status(&po->rx_ring);
+ }
+
+drop_n_restore:
+ if (skb_head != skb->data && skb_shared(skb)) {
+ skb->data = skb_head;
+ skb->len = skb_len;
+ }
+drop:
+ kfree_skb(skb);
+ return 0;
+
+ring_is_full:
+ po->stats.stats1.tp_drops++;
+ spin_unlock(&sk->sk_receive_queue.lock);
+
+ sk->sk_data_ready(sk);
+ kfree_skb(copy_skb);
+ goto drop_n_restore;
+}
+
+static void tpacket_destruct_skb(struct sk_buff *skb)
+{
+ struct packet_sock *po = pkt_sk(skb->sk);
+
+ if (likely(po->tx_ring.pg_vec)) {
+ void *ph;
+ __u32 ts;
+
+ ph = skb_shinfo(skb)->destructor_arg;
+ packet_dec_pending(&po->tx_ring);
+
+ ts = __packet_set_timestamp(po, ph, skb);
+ __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
+ }
+
+ sock_wfree(skb);
+}
+
+static bool ll_header_truncated(const struct net_device *dev, int len)
+{
+ /* net device doesn't like empty head */
+ if (unlikely(len <= dev->hard_header_len)) {
+ net_warn_ratelimited("%s: packet size is too short (%d <= %d)\n",
+ current->comm, len, dev->hard_header_len);
+ return true;
+ }
+
+ return false;
+}
+
+static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
+ void *frame, struct net_device *dev, int size_max,
+ __be16 proto, unsigned char *addr, int hlen)
+{
+ union tpacket_uhdr ph;
+ int to_write, offset, len, tp_len, nr_frags, len_max;
+ struct socket *sock = po->sk.sk_socket;
+ struct page *page;
+ void *data;
+ int err;
+
+ ph.raw = frame;
+
+ skb->protocol = proto;
+ skb->dev = dev;
+ skb->priority = po->sk.sk_priority;
+ skb->mark = po->sk.sk_mark;
+ sock_tx_timestamp(&po->sk, &skb_shinfo(skb)->tx_flags);
+ skb_shinfo(skb)->destructor_arg = ph.raw;
+
+ switch (po->tp_version) {
+ case TPACKET_V2:
+ tp_len = ph.h2->tp_len;
+ break;
+ default:
+ tp_len = ph.h1->tp_len;
+ break;
+ }
+ if (unlikely(tp_len > size_max)) {
+ pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
+ return -EMSGSIZE;
+ }
+
+ skb_reserve(skb, hlen);
+ skb_reset_network_header(skb);
+
+ if (!packet_use_direct_xmit(po))
+ skb_probe_transport_header(skb, 0);
+ if (unlikely(po->tp_tx_has_off)) {
+ int off_min, off_max, off;
+ off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
+ off_max = po->tx_ring.frame_size - tp_len;
+ if (sock->type == SOCK_DGRAM) {
+ switch (po->tp_version) {
+ case TPACKET_V2:
+ off = ph.h2->tp_net;
+ break;
+ default:
+ off = ph.h1->tp_net;
+ break;
+ }
+ } else {
+ switch (po->tp_version) {
+ case TPACKET_V2:
+ off = ph.h2->tp_mac;
+ break;
+ default:
+ off = ph.h1->tp_mac;
+ break;
+ }
+ }
+ if (unlikely((off < off_min) || (off_max < off)))
+ return -EINVAL;
+ data = ph.raw + off;
+ } else {
+ data = ph.raw + po->tp_hdrlen - sizeof(struct sockaddr_ll);
+ }
+ to_write = tp_len;
+
+ if (sock->type == SOCK_DGRAM) {
+ err = dev_hard_header(skb, dev, ntohs(proto), addr,
+ NULL, tp_len);
+ if (unlikely(err < 0))
+ return -EINVAL;
+ } else if (dev->hard_header_len) {
+ if (ll_header_truncated(dev, tp_len))
+ return -EINVAL;
+
+ skb_push(skb, dev->hard_header_len);
+ err = skb_store_bits(skb, 0, data,
+ dev->hard_header_len);
+ if (unlikely(err))
+ return err;
+
+ data += dev->hard_header_len;
+ to_write -= dev->hard_header_len;
+ }
+
+ offset = offset_in_page(data);
+ len_max = PAGE_SIZE - offset;
+ len = ((to_write > len_max) ? len_max : to_write);
+
+ skb->data_len = to_write;
+ skb->len += to_write;
+ skb->truesize += to_write;
+ atomic_add(to_write, &po->sk.sk_wmem_alloc);
+
+ while (likely(to_write)) {
+ nr_frags = skb_shinfo(skb)->nr_frags;
+
+ if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
+ pr_err("Packet exceed the number of skb frags(%lu)\n",
+ MAX_SKB_FRAGS);
+ return -EFAULT;
+ }
+
+ page = pgv_to_page(data);
+ data += len;
+ flush_dcache_page(page);
+ get_page(page);
+ skb_fill_page_desc(skb, nr_frags, page, offset, len);
+ to_write -= len;
+ offset = 0;
+ len_max = PAGE_SIZE;
+ len = ((to_write > len_max) ? len_max : to_write);
+ }
+
+ return tp_len;
+}
+
+static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
+{
+ struct sk_buff *skb;
+ struct net_device *dev;
+ __be16 proto;
+ int err, reserve = 0;
+ void *ph;
+ DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
+ bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
+ int tp_len, size_max;
+ unsigned char *addr;
+ int len_sum = 0;
+ int status = TP_STATUS_AVAILABLE;
+ int hlen, tlen;
+
+ mutex_lock(&po->pg_vec_lock);
+
+ if (likely(saddr == NULL)) {
+ dev = packet_cached_dev_get(po);
+ proto = po->num;
+ addr = NULL;
+ } else {
+ err = -EINVAL;
+ if (msg->msg_namelen < sizeof(struct sockaddr_ll))
+ goto out;
+ if (msg->msg_namelen < (saddr->sll_halen
+ + offsetof(struct sockaddr_ll,
+ sll_addr)))
+ goto out;
+ proto = saddr->sll_protocol;
+ addr = saddr->sll_addr;
+ dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
+ }
+
+ err = -ENXIO;
+ if (unlikely(dev == NULL))
+ goto out;
+ err = -ENETDOWN;
+ if (unlikely(!(dev->flags & IFF_UP)))
+ goto out_put;
+
+ reserve = dev->hard_header_len + VLAN_HLEN;
+ size_max = po->tx_ring.frame_size
+ - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
+
+ if (size_max > dev->mtu + reserve)
+ size_max = dev->mtu + reserve;
+
+ do {
+ ph = packet_current_frame(po, &po->tx_ring,
+ TP_STATUS_SEND_REQUEST);
+ if (unlikely(ph == NULL)) {
+ if (need_wait && need_resched())
+ schedule();
+ continue;
+ }
+
+ status = TP_STATUS_SEND_REQUEST;
+ hlen = LL_RESERVED_SPACE(dev);
+ tlen = dev->needed_tailroom;
+ skb = sock_alloc_send_skb(&po->sk,
+ hlen + tlen + sizeof(struct sockaddr_ll),
+ !need_wait, &err);
+
+ if (unlikely(skb == NULL)) {
+ /* we assume the socket was initially writeable ... */
+ if (likely(len_sum > 0))
+ err = len_sum;
+ goto out_status;
+ }
+ tp_len = tpacket_fill_skb(po, skb, ph, dev, size_max, proto,
+ addr, hlen);
+ if (tp_len > dev->mtu + dev->hard_header_len) {
+ struct ethhdr *ehdr;
+ /* Earlier code assumed this would be a VLAN pkt,
+ * double-check this now that we have the actual
+ * packet in hand.
+ */
+
+ skb_reset_mac_header(skb);
+ ehdr = eth_hdr(skb);
+ if (ehdr->h_proto != htons(ETH_P_8021Q))
+ tp_len = -EMSGSIZE;
+ }
+ if (unlikely(tp_len < 0)) {
+ if (po->tp_loss) {
+ __packet_set_status(po, ph,
+ TP_STATUS_AVAILABLE);
+ packet_increment_head(&po->tx_ring);
+ kfree_skb(skb);
+ continue;
+ } else {
+ status = TP_STATUS_WRONG_FORMAT;
+ err = tp_len;
+ goto out_status;
+ }
+ }
+
+ packet_pick_tx_queue(dev, skb);
+
+ skb->destructor = tpacket_destruct_skb;
+ __packet_set_status(po, ph, TP_STATUS_SENDING);
+ packet_inc_pending(&po->tx_ring);
+
+ status = TP_STATUS_SEND_REQUEST;
+ err = po->xmit(skb);
+ if (unlikely(err > 0)) {
+ err = net_xmit_errno(err);
+ if (err && __packet_get_status(po, ph) ==
+ TP_STATUS_AVAILABLE) {
+ /* skb was destructed already */
+ skb = NULL;
+ goto out_status;
+ }
+ /*
+ * skb was dropped but not destructed yet;
+ * let's treat it like congestion or err < 0
+ */
+ err = 0;
+ }
+ packet_increment_head(&po->tx_ring);
+ len_sum += tp_len;
+ } while (likely((ph != NULL) ||
+ /* Note: packet_read_pending() might be slow if we have
+ * to call it as it's per_cpu variable, but in fast-path
+ * we already short-circuit the loop with the first
+ * condition, and luckily don't have to go that path
+ * anyway.
+ */
+ (need_wait && packet_read_pending(&po->tx_ring))));
+
+ err = len_sum;
+ goto out_put;
+
+out_status:
+ __packet_set_status(po, ph, status);
+ kfree_skb(skb);
+out_put:
+ dev_put(dev);
+out:
+ mutex_unlock(&po->pg_vec_lock);
+ return err;
+}
+
+static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
+ size_t reserve, size_t len,
+ size_t linear, int noblock,
+ int *err)
+{
+ struct sk_buff *skb;
+
+ /* Under a page? Don't bother with paged skb. */
+ if (prepad + len < PAGE_SIZE || !linear)
+ linear = len;
+
+ skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
+ err, 0);
+ if (!skb)
+ return NULL;
+
+ skb_reserve(skb, reserve);
+ skb_put(skb, linear);
+ skb->data_len = len - linear;
+ skb->len += len - linear;
+
+ return skb;
+}
+
+static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
+{
+ struct sock *sk = sock->sk;
+ DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
+ struct sk_buff *skb;
+ struct net_device *dev;
+ __be16 proto;
+ unsigned char *addr;
+ int err, reserve = 0;
+ struct virtio_net_hdr vnet_hdr = { 0 };
+ int offset = 0;
+ int vnet_hdr_len;
+ struct packet_sock *po = pkt_sk(sk);
+ unsigned short gso_type = 0;
+ int hlen, tlen;
+ int extra_len = 0;
+ ssize_t n;
+
+ /*
+ * Get and verify the address.
+ */
+
+ if (likely(saddr == NULL)) {
+ dev = packet_cached_dev_get(po);
+ proto = po->num;
+ addr = NULL;
+ } else {
+ err = -EINVAL;
+ if (msg->msg_namelen < sizeof(struct sockaddr_ll))
+ goto out;
+ if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
+ goto out;
+ proto = saddr->sll_protocol;
+ addr = saddr->sll_addr;
+ dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
+ }
+
+ err = -ENXIO;
+ if (unlikely(dev == NULL))
+ goto out_unlock;
+ err = -ENETDOWN;
+ if (unlikely(!(dev->flags & IFF_UP)))
+ goto out_unlock;
+
+ if (sock->type == SOCK_RAW)
+ reserve = dev->hard_header_len;
+ if (po->has_vnet_hdr) {
+ vnet_hdr_len = sizeof(vnet_hdr);
+
+ err = -EINVAL;
+ if (len < vnet_hdr_len)
+ goto out_unlock;
+
+ len -= vnet_hdr_len;
+
+ err = -EFAULT;
+ n = copy_from_iter(&vnet_hdr, vnet_hdr_len, &msg->msg_iter);
+ if (n != vnet_hdr_len)
+ goto out_unlock;
+
+ if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
+ (__virtio16_to_cpu(false, vnet_hdr.csum_start) +
+ __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2 >
+ __virtio16_to_cpu(false, vnet_hdr.hdr_len)))
+ vnet_hdr.hdr_len = __cpu_to_virtio16(false,
+ __virtio16_to_cpu(false, vnet_hdr.csum_start) +
+ __virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2);
+
+ err = -EINVAL;
+ if (__virtio16_to_cpu(false, vnet_hdr.hdr_len) > len)
+ goto out_unlock;
+
+ if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
+ switch (vnet_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
+ case VIRTIO_NET_HDR_GSO_TCPV4:
+ gso_type = SKB_GSO_TCPV4;
+ break;
+ case VIRTIO_NET_HDR_GSO_TCPV6:
+ gso_type = SKB_GSO_TCPV6;
+ break;
+ case VIRTIO_NET_HDR_GSO_UDP:
+ gso_type = SKB_GSO_UDP;
+ break;
+ default:
+ goto out_unlock;
+ }
+
+ if (vnet_hdr.gso_type & VIRTIO_NET_HDR_GSO_ECN)
+ gso_type |= SKB_GSO_TCP_ECN;
+
+ if (vnet_hdr.gso_size == 0)
+ goto out_unlock;
+
+ }
+ }
+
+ if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
+ if (!netif_supports_nofcs(dev)) {
+ err = -EPROTONOSUPPORT;
+ goto out_unlock;
+ }
+ extra_len = 4; /* We're doing our own CRC */
+ }
+
+ err = -EMSGSIZE;
+ if (!gso_type && (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
+ goto out_unlock;
+
+ err = -ENOBUFS;
+ hlen = LL_RESERVED_SPACE(dev);
+ tlen = dev->needed_tailroom;
+ skb = packet_alloc_skb(sk, hlen + tlen, hlen, len,
+ __virtio16_to_cpu(false, vnet_hdr.hdr_len),
+ msg->msg_flags & MSG_DONTWAIT, &err);
+ if (skb == NULL)
+ goto out_unlock;
+
+ skb_set_network_header(skb, reserve);
+
+ err = -EINVAL;
+ if (sock->type == SOCK_DGRAM) {
+ offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
+ if (unlikely(offset < 0))
+ goto out_free;
+ } else {
+ if (ll_header_truncated(dev, len))
+ goto out_free;
+ }
+
+ /* Returns -EFAULT on error */
+ err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
+ if (err)
+ goto out_free;
+
+ sock_tx_timestamp(sk, &skb_shinfo(skb)->tx_flags);
+
+ if (!gso_type && (len > dev->mtu + reserve + extra_len)) {
+ /* Earlier code assumed this would be a VLAN pkt,
+ * double-check this now that we have the actual
+ * packet in hand.
+ */
+ struct ethhdr *ehdr;
+ skb_reset_mac_header(skb);
+ ehdr = eth_hdr(skb);
+ if (ehdr->h_proto != htons(ETH_P_8021Q)) {
+ err = -EMSGSIZE;
+ goto out_free;
+ }
+ }
+
+ skb->protocol = proto;
+ skb->dev = dev;
+ skb->priority = sk->sk_priority;
+ skb->mark = sk->sk_mark;
+
+ packet_pick_tx_queue(dev, skb);
+
+ if (po->has_vnet_hdr) {
+ if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
+ u16 s = __virtio16_to_cpu(false, vnet_hdr.csum_start);
+ u16 o = __virtio16_to_cpu(false, vnet_hdr.csum_offset);
+ if (!skb_partial_csum_set(skb, s, o)) {
+ err = -EINVAL;
+ goto out_free;
+ }
+ }
+
+ skb_shinfo(skb)->gso_size =
+ __virtio16_to_cpu(false, vnet_hdr.gso_size);
+ skb_shinfo(skb)->gso_type = gso_type;
+
+ /* Header must be checked, and gso_segs computed. */
+ skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
+ skb_shinfo(skb)->gso_segs = 0;
+
+ len += vnet_hdr_len;
+ }
+
+ if (!packet_use_direct_xmit(po))
+ skb_probe_transport_header(skb, reserve);
+ if (unlikely(extra_len == 4))
+ skb->no_fcs = 1;
+
+ err = po->xmit(skb);
+ if (err > 0 && (err = net_xmit_errno(err)) != 0)
+ goto out_unlock;
+
+ dev_put(dev);
+
+ return len;
+
+out_free:
+ kfree_skb(skb);
+out_unlock:
+ if (dev)
+ dev_put(dev);
+out:
+ return err;
+}
+
+static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
+{
+ struct sock *sk = sock->sk;
+ struct packet_sock *po = pkt_sk(sk);
+
+ if (po->tx_ring.pg_vec)
+ return tpacket_snd(po, msg);
+ else
+ return packet_snd(sock, msg, len);
+}
+
+/*
+ * Close a PACKET socket. This is fairly simple. We immediately go
+ * to 'closed' state and remove our protocol entry in the device list.
+ */
+
+static int packet_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct packet_sock *po;
+ struct net *net;
+ union tpacket_req_u req_u;
+
+ if (!sk)
+ return 0;
+
+ net = sock_net(sk);
+ po = pkt_sk(sk);
+
+ mutex_lock(&net->packet.sklist_lock);
+ sk_del_node_init_rcu(sk);
+ mutex_unlock(&net->packet.sklist_lock);
+
+ preempt_disable();
+ sock_prot_inuse_add(net, sk->sk_prot, -1);
+ preempt_enable();
+
+ spin_lock(&po->bind_lock);
+ unregister_prot_hook(sk, false);
+ packet_cached_dev_reset(po);
+
+ if (po->prot_hook.dev) {
+ dev_put(po->prot_hook.dev);
+ po->prot_hook.dev = NULL;
+ }
+ spin_unlock(&po->bind_lock);
+
+ packet_flush_mclist(sk);
+
+ if (po->rx_ring.pg_vec) {
+ memset(&req_u, 0, sizeof(req_u));
+ packet_set_ring(sk, &req_u, 1, 0);
+ }
+
+ if (po->tx_ring.pg_vec) {
+ memset(&req_u, 0, sizeof(req_u));
+ packet_set_ring(sk, &req_u, 1, 1);
+ }
+
+ fanout_release(sk);
+
+ synchronize_net();
+ /*
+ * Now the socket is dead. No more input will appear.
+ */
+ sock_orphan(sk);
+ sock->sk = NULL;
+
+ /* Purge queues */
+
+ skb_queue_purge(&sk->sk_receive_queue);
+ packet_free_pending(po);
+ sk_refcnt_debug_release(sk);
+
+ sock_put(sk);
+ return 0;
+}
+
+/*
+ * Attach a packet hook.
+ */
+
+static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto)
+{
+ struct packet_sock *po = pkt_sk(sk);
+ const struct net_device *dev_curr;
+ __be16 proto_curr;
+ bool need_rehook;
+
+ if (po->fanout) {
+ if (dev)
+ dev_put(dev);
+
+ return -EINVAL;
+ }
+
+ lock_sock(sk);
+ spin_lock(&po->bind_lock);
+
+ proto_curr = po->prot_hook.type;
+ dev_curr = po->prot_hook.dev;
+
+ need_rehook = proto_curr != proto || dev_curr != dev;
+
+ if (need_rehook) {
+ unregister_prot_hook(sk, true);
+
+ po->num = proto;
+ po->prot_hook.type = proto;
+
+ if (po->prot_hook.dev)
+ dev_put(po->prot_hook.dev);
+
+ po->prot_hook.dev = dev;
+
+ po->ifindex = dev ? dev->ifindex : 0;
+ packet_cached_dev_assign(po, dev);
+ }
+
+ if (proto == 0 || !need_rehook)
+ goto out_unlock;
+
+ if (!dev || (dev->flags & IFF_UP)) {
+ register_prot_hook(sk);
+ } else {
+ sk->sk_err = ENETDOWN;
+ if (!sock_flag(sk, SOCK_DEAD))
+ sk->sk_error_report(sk);
+ }
+
+out_unlock:
+ spin_unlock(&po->bind_lock);
+ release_sock(sk);
+ return 0;
+}
+
+/*
+ * Bind a packet socket to a device
+ */
+
+static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
+ int addr_len)
+{
+ struct sock *sk = sock->sk;
+ char name[15];
+ struct net_device *dev;
+ int err = -ENODEV;
+
+ /*
+ * Check legality
+ */
+
+ if (addr_len != sizeof(struct sockaddr))
+ return -EINVAL;
+ strlcpy(name, uaddr->sa_data, sizeof(name));
+
+ dev = dev_get_by_name(sock_net(sk), name);
+ if (dev)
+ err = packet_do_bind(sk, dev, pkt_sk(sk)->num);
+ return err;
+}
+
+static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
+{
+ struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
+ struct sock *sk = sock->sk;
+ struct net_device *dev = NULL;
+ int err;
+
+
+ /*
+ * Check legality
+ */
+
+ if (addr_len < sizeof(struct sockaddr_ll))
+ return -EINVAL;
+ if (sll->sll_family != AF_PACKET)
+ return -EINVAL;
+
+ if (sll->sll_ifindex) {
+ err = -ENODEV;
+ dev = dev_get_by_index(sock_net(sk), sll->sll_ifindex);
+ if (dev == NULL)
+ goto out;
+ }
+ err = packet_do_bind(sk, dev, sll->sll_protocol ? : pkt_sk(sk)->num);
+
+out:
+ return err;
+}
+
+static struct proto packet_proto = {
+ .name = "PACKET",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct packet_sock),
+};
+
+/*
+ * Create a packet of type SOCK_PACKET.
+ */
+
+static int packet_create(struct net *net, struct socket *sock, int protocol,
+ int kern)
+{
+ struct sock *sk;
+ struct packet_sock *po;
+ __be16 proto = (__force __be16)protocol; /* weird, but documented */
+ int err;
+
+ if (!ns_capable(net->user_ns, CAP_NET_RAW))
+ return -EPERM;
+ if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
+ sock->type != SOCK_PACKET)
+ return -ESOCKTNOSUPPORT;
+
+ sock->state = SS_UNCONNECTED;
+
+ err = -ENOBUFS;
+ sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto);
+ if (sk == NULL)
+ goto out;
+
+ sock->ops = &packet_ops;
+ if (sock->type == SOCK_PACKET)
+ sock->ops = &packet_ops_spkt;
+
+ sock_init_data(sock, sk);
+
+ po = pkt_sk(sk);
+ sk->sk_family = PF_PACKET;
+ po->num = proto;
+ po->xmit = dev_queue_xmit;
+
+ err = packet_alloc_pending(po);
+ if (err)
+ goto out2;
+
+ packet_cached_dev_reset(po);
+
+ sk->sk_destruct = packet_sock_destruct;
+ sk_refcnt_debug_inc(sk);
+
+ /*
+ * Attach a protocol block
+ */
+
+ spin_lock_init(&po->bind_lock);
+ mutex_init(&po->pg_vec_lock);
+ po->prot_hook.func = packet_rcv;
+
+ if (sock->type == SOCK_PACKET)
+ po->prot_hook.func = packet_rcv_spkt;
+
+ po->prot_hook.af_packet_priv = sk;
+
+ if (proto) {
+ po->prot_hook.type = proto;
+ register_prot_hook(sk);
+ }
+
+ mutex_lock(&net->packet.sklist_lock);
+ sk_add_node_rcu(sk, &net->packet.sklist);
+ mutex_unlock(&net->packet.sklist_lock);
+
+ preempt_disable();
+ sock_prot_inuse_add(net, &packet_proto, 1);
+ preempt_enable();
+
+ return 0;
+out2:
+ sk_free(sk);
+out:
+ return err;
+}
+
+/*
+ * Pull a packet from our receive queue and hand it to the user.
+ * If necessary we block.
+ */
+
+static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
+ int flags)
+{
+ struct sock *sk = sock->sk;
+ struct sk_buff *skb;
+ int copied, err;
+ int vnet_hdr_len = 0;
+ unsigned int origlen = 0;
+
+ err = -EINVAL;
+ if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
+ goto out;
+
+#if 0
+ /* What error should we return now? EUNATTACH? */
+ if (pkt_sk(sk)->ifindex < 0)
+ return -ENODEV;
+#endif
+
+ if (flags & MSG_ERRQUEUE) {
+ err = sock_recv_errqueue(sk, msg, len,
+ SOL_PACKET, PACKET_TX_TIMESTAMP);
+ goto out;
+ }
+
+ /*
+ * Call the generic datagram receiver. This handles all sorts
+ * of horrible races and re-entrancy so we can forget about it
+ * in the protocol layers.
+ *
+ * Now it will return ENETDOWN, if device have just gone down,
+ * but then it will block.
+ */
+
+ skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
+
+ /*
+ * An error occurred so return it. Because skb_recv_datagram()
+ * handles the blocking we don't see and worry about blocking
+ * retries.
+ */
+
+ if (skb == NULL)
+ goto out;
+
+ if (pkt_sk(sk)->has_vnet_hdr) {
+ struct virtio_net_hdr vnet_hdr = { 0 };
+
+ err = -EINVAL;
+ vnet_hdr_len = sizeof(vnet_hdr);
+ if (len < vnet_hdr_len)
+ goto out_free;
+
+ len -= vnet_hdr_len;
+
+ if (skb_is_gso(skb)) {
+ struct skb_shared_info *sinfo = skb_shinfo(skb);
+
+ /* This is a hint as to how much should be linear. */
+ vnet_hdr.hdr_len =
+ __cpu_to_virtio16(false, skb_headlen(skb));
+ vnet_hdr.gso_size =
+ __cpu_to_virtio16(false, sinfo->gso_size);
+ if (sinfo->gso_type & SKB_GSO_TCPV4)
+ vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
+ else if (sinfo->gso_type & SKB_GSO_TCPV6)
+ vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
+ else if (sinfo->gso_type & SKB_GSO_UDP)
+ vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_UDP;
+ else if (sinfo->gso_type & SKB_GSO_FCOE)
+ goto out_free;
+ else
+ BUG();
+ if (sinfo->gso_type & SKB_GSO_TCP_ECN)
+ vnet_hdr.gso_type |= VIRTIO_NET_HDR_GSO_ECN;
+ } else
+ vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE;
+
+ if (skb->ip_summed == CHECKSUM_PARTIAL) {
+ vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
+ vnet_hdr.csum_start = __cpu_to_virtio16(false,
+ skb_checksum_start_offset(skb));
+ vnet_hdr.csum_offset = __cpu_to_virtio16(false,
+ skb->csum_offset);
+ } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
+ vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;
+ } /* else everything is zero */
+
+ err = memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_len);
+ if (err < 0)
+ goto out_free;
+ }
+
+ /* You lose any data beyond the buffer you gave. If it worries
+ * a user program they can ask the device for its MTU
+ * anyway.
+ */
+ copied = skb->len;
+ if (copied > len) {
+ copied = len;
+ msg->msg_flags |= MSG_TRUNC;
+ }
+
+ err = skb_copy_datagram_msg(skb, 0, msg, copied);
+ if (err)
+ goto out_free;
+
+ if (sock->type != SOCK_PACKET) {
+ struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
+
+ /* Original length was stored in sockaddr_ll fields */
+ origlen = PACKET_SKB_CB(skb)->sa.origlen;
+ sll->sll_family = AF_PACKET;
+ sll->sll_protocol = skb->protocol;
+ }
+
+ sock_recv_ts_and_drops(msg, sk, skb);
+
+ if (msg->msg_name) {
+ /* If the address length field is there to be filled
+ * in, we fill it in now.
+ */
+ if (sock->type == SOCK_PACKET) {
+ __sockaddr_check_size(sizeof(struct sockaddr_pkt));
+ msg->msg_namelen = sizeof(struct sockaddr_pkt);
+ } else {
+ struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
+
+ msg->msg_namelen = sll->sll_halen +
+ offsetof(struct sockaddr_ll, sll_addr);
+ }
+ memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa,
+ msg->msg_namelen);
+ }
+
+ if (pkt_sk(sk)->auxdata) {
+ struct tpacket_auxdata aux;
+
+ aux.tp_status = TP_STATUS_USER;
+ if (skb->ip_summed == CHECKSUM_PARTIAL)
+ aux.tp_status |= TP_STATUS_CSUMNOTREADY;
+ else if (skb->pkt_type != PACKET_OUTGOING &&
+ (skb->ip_summed == CHECKSUM_COMPLETE ||
+ skb_csum_unnecessary(skb)))
+ aux.tp_status |= TP_STATUS_CSUM_VALID;
+
+ aux.tp_len = origlen;
+ aux.tp_snaplen = skb->len;
+ aux.tp_mac = 0;
+ aux.tp_net = skb_network_offset(skb);
+ if (skb_vlan_tag_present(skb)) {
+ aux.tp_vlan_tci = skb_vlan_tag_get(skb);
+ aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
+ aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
+ } else {
+ aux.tp_vlan_tci = 0;
+ aux.tp_vlan_tpid = 0;
+ }
+ put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
+ }
+
+ /*
+ * Free or return the buffer as appropriate. Again this
+ * hides all the races and re-entrancy issues from us.
+ */
+ err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
+
+out_free:
+ skb_free_datagram(sk, skb);
+out:
+ return err;
+}
+
+static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
+ int *uaddr_len, int peer)
+{
+ struct net_device *dev;
+ struct sock *sk = sock->sk;
+
+ if (peer)
+ return -EOPNOTSUPP;
+
+ uaddr->sa_family = AF_PACKET;
+ memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
+ rcu_read_lock();
+ dev = dev_get_by_index_rcu(sock_net(sk), pkt_sk(sk)->ifindex);
+ if (dev)
+ strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
+ rcu_read_unlock();
+ *uaddr_len = sizeof(*uaddr);
+
+ return 0;
+}
+
+static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
+ int *uaddr_len, int peer)
+{
+ struct net_device *dev;
+ struct sock *sk = sock->sk;
+ struct packet_sock *po = pkt_sk(sk);
+ DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
+
+ if (peer)
+ return -EOPNOTSUPP;
+
+ sll->sll_family = AF_PACKET;
+ sll->sll_ifindex = po->ifindex;
+ sll->sll_protocol = po->num;
+ sll->sll_pkttype = 0;
+ rcu_read_lock();
+ dev = dev_get_by_index_rcu(sock_net(sk), po->ifindex);
+ if (dev) {
+ sll->sll_hatype = dev->type;
+ sll->sll_halen = dev->addr_len;
+ memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
+ } else {
+ sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
+ sll->sll_halen = 0;
+ }
+ rcu_read_unlock();
+ *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
+
+ return 0;
+}
+
+static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
+ int what)
+{
+ switch (i->type) {
+ case PACKET_MR_MULTICAST:
+ if (i->alen != dev->addr_len)
+ return -EINVAL;
+ if (what > 0)
+ return dev_mc_add(dev, i->addr);
+ else
+ return dev_mc_del(dev, i->addr);
+ break;
+ case PACKET_MR_PROMISC:
+ return dev_set_promiscuity(dev, what);
+ case PACKET_MR_ALLMULTI:
+ return dev_set_allmulti(dev, what);
+ case PACKET_MR_UNICAST:
+ if (i->alen != dev->addr_len)
+ return -EINVAL;
+ if (what > 0)
+ return dev_uc_add(dev, i->addr);
+ else
+ return dev_uc_del(dev, i->addr);
+ break;
+ default:
+ break;
+ }
+ return 0;
+}
+
+static void packet_dev_mclist_delete(struct net_device *dev,
+ struct packet_mclist **mlp)
+{
+ struct packet_mclist *ml;
+
+ while ((ml = *mlp) != NULL) {
+ if (ml->ifindex == dev->ifindex) {
+ packet_dev_mc(dev, ml, -1);
+ *mlp = ml->next;
+ kfree(ml);
+ } else
+ mlp = &ml->next;
+ }
+}
+
+static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
+{
+ struct packet_sock *po = pkt_sk(sk);
+ struct packet_mclist *ml, *i;
+ struct net_device *dev;
+ int err;
+
+ rtnl_lock();
+
+ err = -ENODEV;
+ dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
+ if (!dev)
+ goto done;
+
+ err = -EINVAL;
+ if (mreq->mr_alen > dev->addr_len)
+ goto done;
+
+ err = -ENOBUFS;
+ i = kmalloc(sizeof(*i), GFP_KERNEL);
+ if (i == NULL)
+ goto done;
+
+ err = 0;
+ for (ml = po->mclist; ml; ml = ml->next) {
+ if (ml->ifindex == mreq->mr_ifindex &&
+ ml->type == mreq->mr_type &&
+ ml->alen == mreq->mr_alen &&
+ memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
+ ml->count++;
+ /* Free the new element ... */
+ kfree(i);
+ goto done;
+ }
+ }
+
+ i->type = mreq->mr_type;
+ i->ifindex = mreq->mr_ifindex;
+ i->alen = mreq->mr_alen;
+ memcpy(i->addr, mreq->mr_address, i->alen);
+ i->count = 1;
+ i->next = po->mclist;
+ po->mclist = i;
+ err = packet_dev_mc(dev, i, 1);
+ if (err) {
+ po->mclist = i->next;
+ kfree(i);
+ }
+
+done:
+ rtnl_unlock();
+ return err;
+}
+
+static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
+{
+ struct packet_mclist *ml, **mlp;
+
+ rtnl_lock();
+
+ for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
+ if (ml->ifindex == mreq->mr_ifindex &&
+ ml->type == mreq->mr_type &&
+ ml->alen == mreq->mr_alen &&
+ memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
+ if (--ml->count == 0) {
+ struct net_device *dev;
+ *mlp = ml->next;
+ dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
+ if (dev)
+ packet_dev_mc(dev, ml, -1);
+ kfree(ml);
+ }
+ break;
+ }
+ }
+ rtnl_unlock();
+ return 0;
+}
+
+static void packet_flush_mclist(struct sock *sk)
+{
+ struct packet_sock *po = pkt_sk(sk);
+ struct packet_mclist *ml;
+
+ if (!po->mclist)
+ return;
+
+ rtnl_lock();
+ while ((ml = po->mclist) != NULL) {
+ struct net_device *dev;
+
+ po->mclist = ml->next;
+ dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
+ if (dev != NULL)
+ packet_dev_mc(dev, ml, -1);
+ kfree(ml);
+ }
+ rtnl_unlock();
+}
+
+static int
+packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
+{
+ struct sock *sk = sock->sk;
+ struct packet_sock *po = pkt_sk(sk);
+ int ret;
+
+ if (level != SOL_PACKET)
+ return -ENOPROTOOPT;
+
+ switch (optname) {
+ case PACKET_ADD_MEMBERSHIP:
+ case PACKET_DROP_MEMBERSHIP:
+ {
+ struct packet_mreq_max mreq;
+ int len = optlen;
+ memset(&mreq, 0, sizeof(mreq));
+ if (len < sizeof(struct packet_mreq))
+ return -EINVAL;
+ if (len > sizeof(mreq))
+ len = sizeof(mreq);
+ if (copy_from_user(&mreq, optval, len))
+ return -EFAULT;
+ if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
+ return -EINVAL;
+ if (optname == PACKET_ADD_MEMBERSHIP)
+ ret = packet_mc_add(sk, &mreq);
+ else
+ ret = packet_mc_drop(sk, &mreq);
+ return ret;
+ }
+
+ case PACKET_RX_RING:
+ case PACKET_TX_RING:
+ {
+ union tpacket_req_u req_u;
+ int len;
+
+ switch (po->tp_version) {
+ case TPACKET_V1:
+ case TPACKET_V2:
+ len = sizeof(req_u.req);
+ break;
+ case TPACKET_V3:
+ default:
+ len = sizeof(req_u.req3);
+ break;
+ }
+ if (optlen < len)
+ return -EINVAL;
+ if (pkt_sk(sk)->has_vnet_hdr)
+ return -EINVAL;
+ if (copy_from_user(&req_u.req, optval, len))
+ return -EFAULT;
+ return packet_set_ring(sk, &req_u, 0,
+ optname == PACKET_TX_RING);
+ }
+ case PACKET_COPY_THRESH:
+ {
+ int val;
+
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ pkt_sk(sk)->copy_thresh = val;
+ return 0;
+ }
+ case PACKET_VERSION:
+ {
+ int val;
+
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
+ return -EBUSY;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+ switch (val) {
+ case TPACKET_V1:
+ case TPACKET_V2:
+ case TPACKET_V3:
+ po->tp_version = val;
+ return 0;
+ default:
+ return -EINVAL;
+ }
+ }
+ case PACKET_RESERVE:
+ {
+ unsigned int val;
+
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
+ return -EBUSY;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+ po->tp_reserve = val;
+ return 0;
+ }
+ case PACKET_LOSS:
+ {
+ unsigned int val;
+
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
+ return -EBUSY;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+ po->tp_loss = !!val;
+ return 0;
+ }
+ case PACKET_AUXDATA:
+ {
+ int val;
+
+ if (optlen < sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ po->auxdata = !!val;
+ return 0;
+ }
+ case PACKET_ORIGDEV:
+ {
+ int val;
+
+ if (optlen < sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ po->origdev = !!val;
+ return 0;
+ }
+ case PACKET_VNET_HDR:
+ {
+ int val;
+
+ if (sock->type != SOCK_RAW)
+ return -EINVAL;
+ if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
+ return -EBUSY;
+ if (optlen < sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ po->has_vnet_hdr = !!val;
+ return 0;
+ }
+ case PACKET_TIMESTAMP:
+ {
+ int val;
+
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ po->tp_tstamp = val;
+ return 0;
+ }
+ case PACKET_FANOUT:
+ {
+ int val;
+
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ return fanout_add(sk, val & 0xffff, val >> 16);
+ }
+ case PACKET_TX_HAS_OFF:
+ {
+ unsigned int val;
+
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (po->rx_ring.pg_vec || po->tx_ring.pg_vec)
+ return -EBUSY;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+ po->tp_tx_has_off = !!val;
+ return 0;
+ }
+ case PACKET_QDISC_BYPASS:
+ {
+ int val;
+
+ if (optlen != sizeof(val))
+ return -EINVAL;
+ if (copy_from_user(&val, optval, sizeof(val)))
+ return -EFAULT;
+
+ po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
+ return 0;
+ }
+ default:
+ return -ENOPROTOOPT;
+ }
+}
+
+static int packet_getsockopt(struct socket *sock, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ int len;
+ int val, lv = sizeof(val);
+ struct sock *sk = sock->sk;
+ struct packet_sock *po = pkt_sk(sk);
+ void *data = &val;
+ union tpacket_stats_u st;
+
+ if (level != SOL_PACKET)
+ return -ENOPROTOOPT;
+
+ if (get_user(len, optlen))
+ return -EFAULT;
+
+ if (len < 0)
+ return -EINVAL;
+
+ switch (optname) {
+ case PACKET_STATISTICS:
+ spin_lock_bh(&sk->sk_receive_queue.lock);
+ memcpy(&st, &po->stats, sizeof(st));
+ memset(&po->stats, 0, sizeof(po->stats));
+ spin_unlock_bh(&sk->sk_receive_queue.lock);
+
+ if (po->tp_version == TPACKET_V3) {
+ lv = sizeof(struct tpacket_stats_v3);
+ st.stats3.tp_packets += st.stats3.tp_drops;
+ data = &st.stats3;
+ } else {
+ lv = sizeof(struct tpacket_stats);
+ st.stats1.tp_packets += st.stats1.tp_drops;
+ data = &st.stats1;
+ }
+
+ break;
+ case PACKET_AUXDATA:
+ val = po->auxdata;
+ break;
+ case PACKET_ORIGDEV:
+ val = po->origdev;
+ break;
+ case PACKET_VNET_HDR:
+ val = po->has_vnet_hdr;
+ break;
+ case PACKET_VERSION:
+ val = po->tp_version;
+ break;
+ case PACKET_HDRLEN:
+ if (len > sizeof(int))
+ len = sizeof(int);
+ if (copy_from_user(&val, optval, len))
+ return -EFAULT;
+ switch (val) {
+ case TPACKET_V1:
+ val = sizeof(struct tpacket_hdr);
+ break;
+ case TPACKET_V2:
+ val = sizeof(struct tpacket2_hdr);
+ break;
+ case TPACKET_V3:
+ val = sizeof(struct tpacket3_hdr);
+ break;
+ default:
+ return -EINVAL;
+ }
+ break;
+ case PACKET_RESERVE:
+ val = po->tp_reserve;
+ break;
+ case PACKET_LOSS:
+ val = po->tp_loss;
+ break;
+ case PACKET_TIMESTAMP:
+ val = po->tp_tstamp;
+ break;
+ case PACKET_FANOUT:
+ val = (po->fanout ?
+ ((u32)po->fanout->id |
+ ((u32)po->fanout->type << 16) |
+ ((u32)po->fanout->flags << 24)) :
+ 0);
+ break;
+ case PACKET_TX_HAS_OFF:
+ val = po->tp_tx_has_off;
+ break;
+ case PACKET_QDISC_BYPASS:
+ val = packet_use_direct_xmit(po);
+ break;
+ default:
+ return -ENOPROTOOPT;
+ }
+
+ if (len > lv)
+ len = lv;
+ if (put_user(len, optlen))
+ return -EFAULT;
+ if (copy_to_user(optval, data, len))
+ return -EFAULT;
+ return 0;
+}
+
+
+static int packet_notifier(struct notifier_block *this,
+ unsigned long msg, void *ptr)
+{
+ struct sock *sk;
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+ struct net *net = dev_net(dev);
+
+ rcu_read_lock();
+ sk_for_each_rcu(sk, &net->packet.sklist) {
+ struct packet_sock *po = pkt_sk(sk);
+
+ switch (msg) {
+ case NETDEV_UNREGISTER:
+ if (po->mclist)
+ packet_dev_mclist_delete(dev, &po->mclist);
+ /* fallthrough */
+
+ case NETDEV_DOWN:
+ if (dev->ifindex == po->ifindex) {
+ spin_lock(&po->bind_lock);
+ if (po->running) {
+ __unregister_prot_hook(sk, false);
+ sk->sk_err = ENETDOWN;
+ if (!sock_flag(sk, SOCK_DEAD))
+ sk->sk_error_report(sk);
+ }
+ if (msg == NETDEV_UNREGISTER) {
+ packet_cached_dev_reset(po);
+ po->ifindex = -1;
+ if (po->prot_hook.dev)
+ dev_put(po->prot_hook.dev);
+ po->prot_hook.dev = NULL;
+ }
+ spin_unlock(&po->bind_lock);
+ }
+ break;
+ case NETDEV_UP:
+ if (dev->ifindex == po->ifindex) {
+ spin_lock(&po->bind_lock);
+ if (po->num)
+ register_prot_hook(sk);
+ spin_unlock(&po->bind_lock);
+ }
+ break;
+ }
+ }
+ rcu_read_unlock();
+ return NOTIFY_DONE;
+}
+
+
+static int packet_ioctl(struct socket *sock, unsigned int cmd,
+ unsigned long arg)
+{
+ struct sock *sk = sock->sk;
+
+ switch (cmd) {
+ case SIOCOUTQ:
+ {
+ int amount = sk_wmem_alloc_get(sk);
+
+ return put_user(amount, (int __user *)arg);
+ }
+ case SIOCINQ:
+ {
+ struct sk_buff *skb;
+ int amount = 0;
+
+ spin_lock_bh(&sk->sk_receive_queue.lock);
+ skb = skb_peek(&sk->sk_receive_queue);
+ if (skb)
+ amount = skb->len;
+ spin_unlock_bh(&sk->sk_receive_queue.lock);
+ return put_user(amount, (int __user *)arg);
+ }
+ case SIOCGSTAMP:
+ return sock_get_timestamp(sk, (struct timeval __user *)arg);
+ case SIOCGSTAMPNS:
+ return sock_get_timestampns(sk, (struct timespec __user *)arg);
+
+#ifdef CONFIG_INET
+ case SIOCADDRT:
+ case SIOCDELRT:
+ case SIOCDARP:
+ case SIOCGARP:
+ case SIOCSARP:
+ case SIOCGIFADDR:
+ case SIOCSIFADDR:
+ case SIOCGIFBRDADDR:
+ case SIOCSIFBRDADDR:
+ case SIOCGIFNETMASK:
+ case SIOCSIFNETMASK:
+ case SIOCGIFDSTADDR:
+ case SIOCSIFDSTADDR:
+ case SIOCSIFFLAGS:
+ return inet_dgram_ops.ioctl(sock, cmd, arg);
+#endif
+
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return 0;
+}
+
+static unsigned int packet_poll(struct file *file, struct socket *sock,
+ poll_table *wait)
+{
+ struct sock *sk = sock->sk;
+ struct packet_sock *po = pkt_sk(sk);
+ unsigned int mask = datagram_poll(file, sock, wait);
+
+ spin_lock_bh(&sk->sk_receive_queue.lock);
+ if (po->rx_ring.pg_vec) {
+ if (!packet_previous_rx_frame(po, &po->rx_ring,
+ TP_STATUS_KERNEL))
+ mask |= POLLIN | POLLRDNORM;
+ }
+ spin_unlock_bh(&sk->sk_receive_queue.lock);
+ spin_lock_bh(&sk->sk_write_queue.lock);
+ if (po->tx_ring.pg_vec) {
+ if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
+ mask |= POLLOUT | POLLWRNORM;
+ }
+ spin_unlock_bh(&sk->sk_write_queue.lock);
+ return mask;
+}
+
+
+/* Dirty? Well, I still did not learn better way to account
+ * for user mmaps.
+ */
+
+static void packet_mm_open(struct vm_area_struct *vma)
+{
+ struct file *file = vma->vm_file;
+ struct socket *sock = file->private_data;
+ struct sock *sk = sock->sk;
+
+ if (sk)
+ atomic_inc(&pkt_sk(sk)->mapped);
+}
+
+static void packet_mm_close(struct vm_area_struct *vma)
+{
+ struct file *file = vma->vm_file;
+ struct socket *sock = file->private_data;
+ struct sock *sk = sock->sk;
+
+ if (sk)
+ atomic_dec(&pkt_sk(sk)->mapped);
+}
+
+static const struct vm_operations_struct packet_mmap_ops = {
+ .open = packet_mm_open,
+ .close = packet_mm_close,
+};
+
+static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
+ unsigned int len)
+{
+ int i;
+
+ for (i = 0; i < len; i++) {
+ if (likely(pg_vec[i].buffer)) {
+ if (is_vmalloc_addr(pg_vec[i].buffer))
+ vfree(pg_vec[i].buffer);
+ else
+ free_pages((unsigned long)pg_vec[i].buffer,
+ order);
+ pg_vec[i].buffer = NULL;
+ }
+ }
+ kfree(pg_vec);
+}
+
+static char *alloc_one_pg_vec_page(unsigned long order)
+{
+ char *buffer;
+ gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
+ __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
+
+ buffer = (char *) __get_free_pages(gfp_flags, order);
+ if (buffer)
+ return buffer;
+
+ /* __get_free_pages failed, fall back to vmalloc */
+ buffer = vzalloc((1 << order) * PAGE_SIZE);
+ if (buffer)
+ return buffer;
+
+ /* vmalloc failed, lets dig into swap here */
+ gfp_flags &= ~__GFP_NORETRY;
+ buffer = (char *) __get_free_pages(gfp_flags, order);
+ if (buffer)
+ return buffer;
+
+ /* complete and utter failure */
+ return NULL;
+}
+
+static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
+{
+ unsigned int block_nr = req->tp_block_nr;
+ struct pgv *pg_vec;
+ int i;
+
+ pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL);
+ if (unlikely(!pg_vec))
+ goto out;
+
+ for (i = 0; i < block_nr; i++) {
+ pg_vec[i].buffer = alloc_one_pg_vec_page(order);
+ if (unlikely(!pg_vec[i].buffer))
+ goto out_free_pgvec;
+ }
+
+out:
+ return pg_vec;
+
+out_free_pgvec:
+ free_pg_vec(pg_vec, order, block_nr);
+ pg_vec = NULL;
+ goto out;
+}
+
+static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
+ int closing, int tx_ring)
+{
+ struct pgv *pg_vec = NULL;
+ struct packet_sock *po = pkt_sk(sk);
+ int was_running, order = 0;
+ struct packet_ring_buffer *rb;
+ struct sk_buff_head *rb_queue;
+ __be16 num;
+ int err = -EINVAL;
+ /* Added to avoid minimal code churn */
+ struct tpacket_req *req = &req_u->req;
+
+ /* Opening a Tx-ring is NOT supported in TPACKET_V3 */
+ if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
+ WARN(1, "Tx-ring is not supported.\n");
+ goto out;
+ }
+
+ rb = tx_ring ? &po->tx_ring : &po->rx_ring;
+ rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
+
+ err = -EBUSY;
+ if (!closing) {
+ if (atomic_read(&po->mapped))
+ goto out;
+ if (packet_read_pending(rb))
+ goto out;
+ }
+
+ if (req->tp_block_nr) {
+ /* Sanity tests and some calculations */
+ err = -EBUSY;
+ if (unlikely(rb->pg_vec))
+ goto out;
+
+ switch (po->tp_version) {
+ case TPACKET_V1:
+ po->tp_hdrlen = TPACKET_HDRLEN;
+ break;
+ case TPACKET_V2:
+ po->tp_hdrlen = TPACKET2_HDRLEN;
+ break;
+ case TPACKET_V3:
+ po->tp_hdrlen = TPACKET3_HDRLEN;
+ break;
+ }
+
+ err = -EINVAL;
+ if (unlikely((int)req->tp_block_size <= 0))
+ goto out;
+ if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
+ goto out;
+ if (po->tp_version >= TPACKET_V3 &&
+ (int)(req->tp_block_size -
+ BLK_PLUS_PRIV(req_u->req3.tp_sizeof_priv)) <= 0)
+ goto out;
+ if (unlikely(req->tp_frame_size < po->tp_hdrlen +
+ po->tp_reserve))
+ goto out;
+ if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
+ goto out;
+
+ rb->frames_per_block = req->tp_block_size/req->tp_frame_size;
+ if (unlikely(rb->frames_per_block <= 0))
+ goto out;
+ if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
+ req->tp_frame_nr))
+ goto out;
+
+ err = -ENOMEM;
+ order = get_order(req->tp_block_size);
+ pg_vec = alloc_pg_vec(req, order);
+ if (unlikely(!pg_vec))
+ goto out;
+ switch (po->tp_version) {
+ case TPACKET_V3:
+ /* Transmit path is not supported. We checked
+ * it above but just being paranoid
+ */
+ if (!tx_ring)
+ init_prb_bdqc(po, rb, pg_vec, req_u, tx_ring);
+ break;
+ default:
+ break;
+ }
+ }
+ /* Done */
+ else {
+ err = -EINVAL;
+ if (unlikely(req->tp_frame_nr))
+ goto out;
+ }
+
+ lock_sock(sk);
+
+ /* Detach socket from network */
+ spin_lock(&po->bind_lock);
+ was_running = po->running;
+ num = po->num;
+ if (was_running) {
+ po->num = 0;
+ __unregister_prot_hook(sk, false);
+ }
+ spin_unlock(&po->bind_lock);
+
+ synchronize_net();
+
+ err = -EBUSY;
+ mutex_lock(&po->pg_vec_lock);
+ if (closing || atomic_read(&po->mapped) == 0) {
+ err = 0;
+ spin_lock_bh(&rb_queue->lock);
+ swap(rb->pg_vec, pg_vec);
+ rb->frame_max = (req->tp_frame_nr - 1);
+ rb->head = 0;
+ rb->frame_size = req->tp_frame_size;
+ spin_unlock_bh(&rb_queue->lock);
+
+ swap(rb->pg_vec_order, order);
+ swap(rb->pg_vec_len, req->tp_block_nr);
+
+ rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
+ po->prot_hook.func = (po->rx_ring.pg_vec) ?
+ tpacket_rcv : packet_rcv;
+ skb_queue_purge(rb_queue);
+ if (atomic_read(&po->mapped))
+ pr_err("packet_mmap: vma is busy: %d\n",
+ atomic_read(&po->mapped));
+ }
+ mutex_unlock(&po->pg_vec_lock);
+
+ spin_lock(&po->bind_lock);
+ if (was_running) {
+ po->num = num;
+ register_prot_hook(sk);
+ }
+ spin_unlock(&po->bind_lock);
+ if (closing && (po->tp_version > TPACKET_V2)) {
+ /* Because we don't support block-based V3 on tx-ring */
+ if (!tx_ring)
+ prb_shutdown_retire_blk_timer(po, tx_ring, rb_queue);
+ }
+ release_sock(sk);
+
+ if (pg_vec)
+ free_pg_vec(pg_vec, order, req->tp_block_nr);
+out:
+ return err;
+}
+
+static int packet_mmap(struct file *file, struct socket *sock,
+ struct vm_area_struct *vma)
+{
+ struct sock *sk = sock->sk;
+ struct packet_sock *po = pkt_sk(sk);
+ unsigned long size, expected_size;
+ struct packet_ring_buffer *rb;
+ unsigned long start;
+ int err = -EINVAL;
+ int i;
+
+ if (vma->vm_pgoff)
+ return -EINVAL;
+
+ mutex_lock(&po->pg_vec_lock);
+
+ expected_size = 0;
+ for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
+ if (rb->pg_vec) {
+ expected_size += rb->pg_vec_len
+ * rb->pg_vec_pages
+ * PAGE_SIZE;
+ }
+ }
+
+ if (expected_size == 0)
+ goto out;
+
+ size = vma->vm_end - vma->vm_start;
+ if (size != expected_size)
+ goto out;
+
+ start = vma->vm_start;
+ for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
+ if (rb->pg_vec == NULL)
+ continue;
+
+ for (i = 0; i < rb->pg_vec_len; i++) {
+ struct page *page;
+ void *kaddr = rb->pg_vec[i].buffer;
+ int pg_num;
+
+ for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
+ page = pgv_to_page(kaddr);
+ err = vm_insert_page(vma, start, page);
+ if (unlikely(err))
+ goto out;
+ start += PAGE_SIZE;
+ kaddr += PAGE_SIZE;
+ }
+ }
+ }
+
+ atomic_inc(&po->mapped);
+ vma->vm_ops = &packet_mmap_ops;
+ err = 0;
+
+out:
+ mutex_unlock(&po->pg_vec_lock);
+ return err;
+}
+
+static const struct proto_ops packet_ops_spkt = {
+ .family = PF_PACKET,
+ .owner = THIS_MODULE,
+ .release = packet_release,
+ .bind = packet_bind_spkt,
+ .connect = sock_no_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = packet_getname_spkt,
+ .poll = datagram_poll,
+ .ioctl = packet_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = sock_no_setsockopt,
+ .getsockopt = sock_no_getsockopt,
+ .sendmsg = packet_sendmsg_spkt,
+ .recvmsg = packet_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static const struct proto_ops packet_ops = {
+ .family = PF_PACKET,
+ .owner = THIS_MODULE,
+ .release = packet_release,
+ .bind = packet_bind,
+ .connect = sock_no_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = packet_getname,
+ .poll = packet_poll,
+ .ioctl = packet_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = packet_setsockopt,
+ .getsockopt = packet_getsockopt,
+ .sendmsg = packet_sendmsg,
+ .recvmsg = packet_recvmsg,
+ .mmap = packet_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static const struct net_proto_family packet_family_ops = {
+ .family = PF_PACKET,
+ .create = packet_create,
+ .owner = THIS_MODULE,
+};
+
+static struct notifier_block packet_netdev_notifier = {
+ .notifier_call = packet_notifier,
+};
+
+#ifdef CONFIG_PROC_FS
+
+static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
+ __acquires(RCU)
+{
+ struct net *net = seq_file_net(seq);
+
+ rcu_read_lock();
+ return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
+}
+
+static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct net *net = seq_file_net(seq);
+ return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
+}
+
+static void packet_seq_stop(struct seq_file *seq, void *v)
+ __releases(RCU)
+{
+ rcu_read_unlock();
+}
+
+static int packet_seq_show(struct seq_file *seq, void *v)
+{
+ if (v == SEQ_START_TOKEN)
+ seq_puts(seq, "sk RefCnt Type Proto Iface R Rmem User Inode\n");
+ else {
+ struct sock *s = sk_entry(v);
+ const struct packet_sock *po = pkt_sk(s);
+
+ seq_printf(seq,
+ "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
+ s,
+ atomic_read(&s->sk_refcnt),
+ s->sk_type,
+ ntohs(po->num),
+ po->ifindex,
+ po->running,
+ atomic_read(&s->sk_rmem_alloc),
+ from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
+ sock_i_ino(s));
+ }
+
+ return 0;
+}
+
+static const struct seq_operations packet_seq_ops = {
+ .start = packet_seq_start,
+ .next = packet_seq_next,
+ .stop = packet_seq_stop,
+ .show = packet_seq_show,
+};
+
+static int packet_seq_open(struct inode *inode, struct file *file)
+{
+ return seq_open_net(inode, file, &packet_seq_ops,
+ sizeof(struct seq_net_private));
+}
+
+static const struct file_operations packet_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = packet_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_net,
+};
+
+#endif
+
+static int __net_init packet_net_init(struct net *net)
+{
+ mutex_init(&net->packet.sklist_lock);
+ INIT_HLIST_HEAD(&net->packet.sklist);
+
+ if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void __net_exit packet_net_exit(struct net *net)
+{
+ remove_proc_entry("packet", net->proc_net);
+}
+
+static struct pernet_operations packet_net_ops = {
+ .init = packet_net_init,
+ .exit = packet_net_exit,
+};
+
+
+static void __exit packet_exit(void)
+{
+ unregister_netdevice_notifier(&packet_netdev_notifier);
+ unregister_pernet_subsys(&packet_net_ops);
+ sock_unregister(PF_PACKET);
+ proto_unregister(&packet_proto);
+}
+
+static int __init packet_init(void)
+{
+ int rc = proto_register(&packet_proto, 0);
+
+ if (rc != 0)
+ goto out;
+
+ sock_register(&packet_family_ops);
+ register_pernet_subsys(&packet_net_ops);
+ register_netdevice_notifier(&packet_netdev_notifier);
+out:
+ return rc;
+}
+
+module_init(packet_init);
+module_exit(packet_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(PF_PACKET);