diff options
Diffstat (limited to 'kernel/net/packet')
| -rw-r--r-- | kernel/net/packet/Kconfig | 24 | ||||
| -rw-r--r-- | kernel/net/packet/Makefile | 7 | ||||
| -rw-r--r-- | kernel/net/packet/af_packet.c | 4177 | ||||
| -rw-r--r-- | kernel/net/packet/diag.c | 265 | ||||
| -rw-r--r-- | kernel/net/packet/internal.h | 125 |
5 files changed, 4598 insertions, 0 deletions
diff --git a/kernel/net/packet/Kconfig b/kernel/net/packet/Kconfig new file mode 100644 index 000000000..cc55b35f8 --- /dev/null +++ b/kernel/net/packet/Kconfig @@ -0,0 +1,24 @@ +# +# Packet configuration +# + +config PACKET + tristate "Packet socket" + ---help--- + The Packet protocol is used by applications which communicate + directly with network devices without an intermediate network + protocol implemented in the kernel, e.g. tcpdump. If you want them + to work, choose Y. + + To compile this driver as a module, choose M here: the module will + be called af_packet. + + If unsure, say Y. + +config PACKET_DIAG + tristate "Packet: sockets monitoring interface" + depends on PACKET + default n + ---help--- + Support for PF_PACKET sockets monitoring interface used by the ss tool. + If unsure, say Y. diff --git a/kernel/net/packet/Makefile b/kernel/net/packet/Makefile new file mode 100644 index 000000000..9df61347a --- /dev/null +++ b/kernel/net/packet/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for the packet AF. +# + +obj-$(CONFIG_PACKET) += af_packet.o +obj-$(CONFIG_PACKET_DIAG) += af_packet_diag.o +af_packet_diag-y += diag.o 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); diff --git a/kernel/net/packet/diag.c b/kernel/net/packet/diag.c new file mode 100644 index 000000000..0ed68f023 --- /dev/null +++ b/kernel/net/packet/diag.c @@ -0,0 +1,265 @@ +#include <linux/module.h> +#include <linux/sock_diag.h> +#include <linux/net.h> +#include <linux/netdevice.h> +#include <linux/packet_diag.h> +#include <linux/percpu.h> +#include <net/net_namespace.h> +#include <net/sock.h> + +#include "internal.h" + +static int pdiag_put_info(const struct packet_sock *po, struct sk_buff *nlskb) +{ + struct packet_diag_info pinfo; + + pinfo.pdi_index = po->ifindex; + pinfo.pdi_version = po->tp_version; + pinfo.pdi_reserve = po->tp_reserve; + pinfo.pdi_copy_thresh = po->copy_thresh; + pinfo.pdi_tstamp = po->tp_tstamp; + + pinfo.pdi_flags = 0; + if (po->running) + pinfo.pdi_flags |= PDI_RUNNING; + if (po->auxdata) + pinfo.pdi_flags |= PDI_AUXDATA; + if (po->origdev) + pinfo.pdi_flags |= PDI_ORIGDEV; + if (po->has_vnet_hdr) + pinfo.pdi_flags |= PDI_VNETHDR; + if (po->tp_loss) + pinfo.pdi_flags |= PDI_LOSS; + + return nla_put(nlskb, PACKET_DIAG_INFO, sizeof(pinfo), &pinfo); +} + +static int pdiag_put_mclist(const struct packet_sock *po, struct sk_buff *nlskb) +{ + struct nlattr *mca; + struct packet_mclist *ml; + + mca = nla_nest_start(nlskb, PACKET_DIAG_MCLIST); + if (!mca) + return -EMSGSIZE; + + rtnl_lock(); + for (ml = po->mclist; ml; ml = ml->next) { + struct packet_diag_mclist *dml; + + dml = nla_reserve_nohdr(nlskb, sizeof(*dml)); + if (!dml) { + rtnl_unlock(); + nla_nest_cancel(nlskb, mca); + return -EMSGSIZE; + } + + dml->pdmc_index = ml->ifindex; + dml->pdmc_type = ml->type; + dml->pdmc_alen = ml->alen; + dml->pdmc_count = ml->count; + BUILD_BUG_ON(sizeof(dml->pdmc_addr) != sizeof(ml->addr)); + memcpy(dml->pdmc_addr, ml->addr, sizeof(ml->addr)); + } + + rtnl_unlock(); + nla_nest_end(nlskb, mca); + + return 0; +} + +static int pdiag_put_ring(struct packet_ring_buffer *ring, int ver, int nl_type, + struct sk_buff *nlskb) +{ + struct packet_diag_ring pdr; + + if (!ring->pg_vec || ((ver > TPACKET_V2) && + (nl_type == PACKET_DIAG_TX_RING))) + return 0; + + pdr.pdr_block_size = ring->pg_vec_pages << PAGE_SHIFT; + pdr.pdr_block_nr = ring->pg_vec_len; + pdr.pdr_frame_size = ring->frame_size; + pdr.pdr_frame_nr = ring->frame_max + 1; + + if (ver > TPACKET_V2) { + pdr.pdr_retire_tmo = ring->prb_bdqc.retire_blk_tov; + pdr.pdr_sizeof_priv = ring->prb_bdqc.blk_sizeof_priv; + pdr.pdr_features = ring->prb_bdqc.feature_req_word; + } else { + pdr.pdr_retire_tmo = 0; + pdr.pdr_sizeof_priv = 0; + pdr.pdr_features = 0; + } + + return nla_put(nlskb, nl_type, sizeof(pdr), &pdr); +} + +static int pdiag_put_rings_cfg(struct packet_sock *po, struct sk_buff *skb) +{ + int ret; + + mutex_lock(&po->pg_vec_lock); + ret = pdiag_put_ring(&po->rx_ring, po->tp_version, + PACKET_DIAG_RX_RING, skb); + if (!ret) + ret = pdiag_put_ring(&po->tx_ring, po->tp_version, + PACKET_DIAG_TX_RING, skb); + mutex_unlock(&po->pg_vec_lock); + + return ret; +} + +static int pdiag_put_fanout(struct packet_sock *po, struct sk_buff *nlskb) +{ + int ret = 0; + + mutex_lock(&fanout_mutex); + if (po->fanout) { + u32 val; + + val = (u32)po->fanout->id | ((u32)po->fanout->type << 16); + ret = nla_put_u32(nlskb, PACKET_DIAG_FANOUT, val); + } + mutex_unlock(&fanout_mutex); + + return ret; +} + +static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, + struct packet_diag_req *req, + bool may_report_filterinfo, + struct user_namespace *user_ns, + u32 portid, u32 seq, u32 flags, int sk_ino) +{ + struct nlmsghdr *nlh; + struct packet_diag_msg *rp; + struct packet_sock *po = pkt_sk(sk); + + nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rp), flags); + if (!nlh) + return -EMSGSIZE; + + rp = nlmsg_data(nlh); + rp->pdiag_family = AF_PACKET; + rp->pdiag_type = sk->sk_type; + rp->pdiag_num = ntohs(po->num); + rp->pdiag_ino = sk_ino; + sock_diag_save_cookie(sk, rp->pdiag_cookie); + + if ((req->pdiag_show & PACKET_SHOW_INFO) && + pdiag_put_info(po, skb)) + goto out_nlmsg_trim; + + if ((req->pdiag_show & PACKET_SHOW_INFO) && + nla_put_u32(skb, PACKET_DIAG_UID, + from_kuid_munged(user_ns, sock_i_uid(sk)))) + goto out_nlmsg_trim; + + if ((req->pdiag_show & PACKET_SHOW_MCLIST) && + pdiag_put_mclist(po, skb)) + goto out_nlmsg_trim; + + if ((req->pdiag_show & PACKET_SHOW_RING_CFG) && + pdiag_put_rings_cfg(po, skb)) + goto out_nlmsg_trim; + + if ((req->pdiag_show & PACKET_SHOW_FANOUT) && + pdiag_put_fanout(po, skb)) + goto out_nlmsg_trim; + + if ((req->pdiag_show & PACKET_SHOW_MEMINFO) && + sock_diag_put_meminfo(sk, skb, PACKET_DIAG_MEMINFO)) + goto out_nlmsg_trim; + + if ((req->pdiag_show & PACKET_SHOW_FILTER) && + sock_diag_put_filterinfo(may_report_filterinfo, sk, skb, + PACKET_DIAG_FILTER)) + goto out_nlmsg_trim; + + nlmsg_end(skb, nlh); + return 0; + +out_nlmsg_trim: + nlmsg_cancel(skb, nlh); + return -EMSGSIZE; +} + +static int packet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + int num = 0, s_num = cb->args[0]; + struct packet_diag_req *req; + struct net *net; + struct sock *sk; + bool may_report_filterinfo; + + net = sock_net(skb->sk); + req = nlmsg_data(cb->nlh); + may_report_filterinfo = netlink_net_capable(cb->skb, CAP_NET_ADMIN); + + mutex_lock(&net->packet.sklist_lock); + sk_for_each(sk, &net->packet.sklist) { + if (!net_eq(sock_net(sk), net)) + continue; + if (num < s_num) + goto next; + + if (sk_diag_fill(sk, skb, req, + may_report_filterinfo, + sk_user_ns(NETLINK_CB(cb->skb).sk), + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, NLM_F_MULTI, + sock_i_ino(sk)) < 0) + goto done; +next: + num++; + } +done: + mutex_unlock(&net->packet.sklist_lock); + cb->args[0] = num; + + return skb->len; +} + +static int packet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h) +{ + int hdrlen = sizeof(struct packet_diag_req); + struct net *net = sock_net(skb->sk); + struct packet_diag_req *req; + + if (nlmsg_len(h) < hdrlen) + return -EINVAL; + + req = nlmsg_data(h); + /* Make it possible to support protocol filtering later */ + if (req->sdiag_protocol) + return -EINVAL; + + if (h->nlmsg_flags & NLM_F_DUMP) { + struct netlink_dump_control c = { + .dump = packet_diag_dump, + }; + return netlink_dump_start(net->diag_nlsk, skb, h, &c); + } else + return -EOPNOTSUPP; +} + +static const struct sock_diag_handler packet_diag_handler = { + .family = AF_PACKET, + .dump = packet_diag_handler_dump, +}; + +static int __init packet_diag_init(void) +{ + return sock_diag_register(&packet_diag_handler); +} + +static void __exit packet_diag_exit(void) +{ + sock_diag_unregister(&packet_diag_handler); +} + +module_init(packet_diag_init); +module_exit(packet_diag_exit); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 17 /* AF_PACKET */); diff --git a/kernel/net/packet/internal.h b/kernel/net/packet/internal.h new file mode 100644 index 000000000..fe6e20cae --- /dev/null +++ b/kernel/net/packet/internal.h @@ -0,0 +1,125 @@ +#ifndef __PACKET_INTERNAL_H__ +#define __PACKET_INTERNAL_H__ + +struct packet_mclist { + struct packet_mclist *next; + int ifindex; + int count; + unsigned short type; + unsigned short alen; + unsigned char addr[MAX_ADDR_LEN]; +}; + +/* kbdq - kernel block descriptor queue */ +struct tpacket_kbdq_core { + struct pgv *pkbdq; + unsigned int feature_req_word; + unsigned int hdrlen; + unsigned char reset_pending_on_curr_blk; + unsigned char delete_blk_timer; + unsigned short kactive_blk_num; + unsigned short blk_sizeof_priv; + + /* last_kactive_blk_num: + * trick to see if user-space has caught up + * in order to avoid refreshing timer when every single pkt arrives. + */ + unsigned short last_kactive_blk_num; + + char *pkblk_start; + char *pkblk_end; + int kblk_size; + unsigned int max_frame_len; + unsigned int knum_blocks; + uint64_t knxt_seq_num; + char *prev; + char *nxt_offset; + struct sk_buff *skb; + + atomic_t blk_fill_in_prog; + + /* Default is set to 8ms */ +#define DEFAULT_PRB_RETIRE_TOV (8) + + unsigned short retire_blk_tov; + unsigned short version; + unsigned long tov_in_jiffies; + + /* timer to retire an outstanding block */ + struct timer_list retire_blk_timer; +}; + +struct pgv { + char *buffer; +}; + +struct packet_ring_buffer { + struct pgv *pg_vec; + + unsigned int head; + unsigned int frames_per_block; + unsigned int frame_size; + unsigned int frame_max; + + unsigned int pg_vec_order; + unsigned int pg_vec_pages; + unsigned int pg_vec_len; + + unsigned int __percpu *pending_refcnt; + + struct tpacket_kbdq_core prb_bdqc; +}; + +extern struct mutex fanout_mutex; +#define PACKET_FANOUT_MAX 256 + +struct packet_fanout { + possible_net_t net; + unsigned int num_members; + u16 id; + u8 type; + u8 flags; + atomic_t rr_cur; + struct list_head list; + struct sock *arr[PACKET_FANOUT_MAX]; + int next[PACKET_FANOUT_MAX]; + spinlock_t lock; + atomic_t sk_ref; + struct packet_type prot_hook ____cacheline_aligned_in_smp; +}; + +struct packet_sock { + /* struct sock has to be the first member of packet_sock */ + struct sock sk; + struct packet_fanout *fanout; + union tpacket_stats_u stats; + struct packet_ring_buffer rx_ring; + struct packet_ring_buffer tx_ring; + int copy_thresh; + spinlock_t bind_lock; + struct mutex pg_vec_lock; + unsigned int running:1, /* prot_hook is attached*/ + auxdata:1, + origdev:1, + has_vnet_hdr:1; + int ifindex; /* bound device */ + __be16 num; + struct packet_mclist *mclist; + atomic_t mapped; + enum tpacket_versions tp_version; + unsigned int tp_hdrlen; + unsigned int tp_reserve; + unsigned int tp_loss:1; + unsigned int tp_tx_has_off:1; + unsigned int tp_tstamp; + struct net_device __rcu *cached_dev; + int (*xmit)(struct sk_buff *skb); + struct packet_type prot_hook ____cacheline_aligned_in_smp; +}; + +static struct packet_sock *pkt_sk(struct sock *sk) +{ + return (struct packet_sock *)sk; +} + +#endif |