Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 1 | /* drivers/net/pppolac.c |
| 2 | * |
| 3 | * Driver for PPP on L2TP Access Concentrator / PPPoLAC Socket (RFC 2661) |
| 4 | * |
| 5 | * Copyright (C) 2009 Google, Inc. |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 6 | * |
| 7 | * This software is licensed under the terms of the GNU General Public |
| 8 | * License version 2, as published by the Free Software Foundation, and |
| 9 | * may be copied, distributed, and modified under those terms. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | */ |
| 16 | |
| 17 | /* This driver handles L2TP data packets between a UDP socket and a PPP channel. |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 18 | * The socket must keep connected, and only one session per socket is permitted. |
| 19 | * Sequencing of outgoing packets is controlled by LNS. Incoming packets with |
| 20 | * sequences are reordered within a sliding window of one second. Currently |
| 21 | * reordering only happens when a packet is received. It is done for simplicity |
| 22 | * since no additional locks or threads are required. This driver only works on |
| 23 | * IPv4 due to the lack of UDP encapsulation support in IPv6. */ |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 24 | |
| 25 | #include <linux/module.h> |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 26 | #include <linux/jiffies.h> |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 27 | #include <linux/workqueue.h> |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 28 | #include <linux/skbuff.h> |
| 29 | #include <linux/file.h> |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 30 | #include <linux/netdevice.h> |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 31 | #include <linux/net.h> |
| 32 | #include <linux/udp.h> |
| 33 | #include <linux/ppp_defs.h> |
| 34 | #include <linux/if_ppp.h> |
| 35 | #include <linux/if_pppox.h> |
| 36 | #include <linux/ppp_channel.h> |
| 37 | #include <net/tcp_states.h> |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 38 | #include <asm/uaccess.h> |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 39 | |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 40 | #define L2TP_CONTROL_BIT 0x80 |
| 41 | #define L2TP_LENGTH_BIT 0x40 |
| 42 | #define L2TP_SEQUENCE_BIT 0x08 |
| 43 | #define L2TP_OFFSET_BIT 0x02 |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 44 | #define L2TP_VERSION 0x02 |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 45 | #define L2TP_VERSION_MASK 0x0F |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 46 | |
| 47 | #define PPP_ADDR 0xFF |
| 48 | #define PPP_CTRL 0x03 |
| 49 | |
| 50 | union unaligned { |
| 51 | __u32 u32; |
| 52 | } __attribute__((packed)); |
| 53 | |
| 54 | static inline union unaligned *unaligned(void *ptr) |
| 55 | { |
| 56 | return (union unaligned *)ptr; |
| 57 | } |
| 58 | |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 59 | struct meta { |
| 60 | __u32 sequence; |
| 61 | __u32 timestamp; |
| 62 | }; |
| 63 | |
| 64 | static inline struct meta *skb_meta(struct sk_buff *skb) |
| 65 | { |
| 66 | return (struct meta *)skb->cb; |
| 67 | } |
| 68 | |
| 69 | /******************************************************************************/ |
| 70 | |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 71 | static int pppolac_recv_core(struct sock *sk_udp, struct sk_buff *skb) |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 72 | { |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 73 | struct sock *sk = (struct sock *)sk_udp->sk_user_data; |
| 74 | struct pppolac_opt *opt = &pppox_sk(sk)->proto.lac; |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 75 | struct meta *meta = skb_meta(skb); |
| 76 | __u32 now = jiffies; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 77 | __u8 bits; |
| 78 | __u8 *ptr; |
| 79 | |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 80 | /* Drop the packet if L2TP header is missing. */ |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 81 | if (skb->len < sizeof(struct udphdr) + 6) |
| 82 | goto drop; |
| 83 | |
| 84 | /* Put it back if it is a control packet. */ |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 85 | if (skb->data[sizeof(struct udphdr)] & L2TP_CONTROL_BIT) |
| 86 | return opt->backlog_rcv(sk_udp, skb); |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 87 | |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 88 | /* Skip UDP header. */ |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 89 | skb_pull(skb, sizeof(struct udphdr)); |
| 90 | |
| 91 | /* Check the version. */ |
| 92 | if ((skb->data[1] & L2TP_VERSION_MASK) != L2TP_VERSION) |
| 93 | goto drop; |
| 94 | bits = skb->data[0]; |
| 95 | ptr = &skb->data[2]; |
| 96 | |
| 97 | /* Check the length if it is present. */ |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 98 | if (bits & L2TP_LENGTH_BIT) { |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 99 | if ((ptr[0] << 8 | ptr[1]) != skb->len) |
| 100 | goto drop; |
| 101 | ptr += 2; |
| 102 | } |
| 103 | |
| 104 | /* Skip all fields including optional ones. */ |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 105 | if (!skb_pull(skb, 6 + (bits & L2TP_SEQUENCE_BIT ? 4 : 0) + |
| 106 | (bits & L2TP_LENGTH_BIT ? 2 : 0) + |
| 107 | (bits & L2TP_OFFSET_BIT ? 2 : 0))) |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 108 | goto drop; |
| 109 | |
| 110 | /* Skip the offset padding if it is present. */ |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 111 | if (bits & L2TP_OFFSET_BIT && |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 112 | !skb_pull(skb, skb->data[-2] << 8 | skb->data[-1])) |
| 113 | goto drop; |
| 114 | |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 115 | /* Check the tunnel and the session. */ |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 116 | if (unaligned(ptr)->u32 != opt->local) |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 117 | goto drop; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 118 | |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 119 | /* Check the sequence if it is present. */ |
| 120 | if (bits & L2TP_SEQUENCE_BIT) { |
| 121 | meta->sequence = ptr[4] << 8 | ptr[5]; |
| 122 | if ((__s16)(meta->sequence - opt->recv_sequence) < 0) |
| 123 | goto drop; |
| 124 | } |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 125 | |
| 126 | /* Skip PPP address and control if they are present. */ |
| 127 | if (skb->len >= 2 && skb->data[0] == PPP_ADDR && |
| 128 | skb->data[1] == PPP_CTRL) |
| 129 | skb_pull(skb, 2); |
| 130 | |
| 131 | /* Fix PPP protocol if it is compressed. */ |
| 132 | if (skb->len >= 1 && skb->data[0] & 1) |
| 133 | skb_push(skb, 1)[0] = 0; |
| 134 | |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 135 | /* Drop the packet if PPP protocol is missing. */ |
| 136 | if (skb->len < 2) |
| 137 | goto drop; |
| 138 | |
| 139 | /* Perform reordering if sequencing is enabled. */ |
| 140 | atomic_set(&opt->sequencing, bits & L2TP_SEQUENCE_BIT); |
| 141 | if (bits & L2TP_SEQUENCE_BIT) { |
| 142 | struct sk_buff *skb1; |
| 143 | |
| 144 | /* Insert the packet into receive queue in order. */ |
| 145 | skb_set_owner_r(skb, sk); |
| 146 | skb_queue_walk(&sk->sk_receive_queue, skb1) { |
| 147 | struct meta *meta1 = skb_meta(skb1); |
| 148 | __s16 order = meta->sequence - meta1->sequence; |
| 149 | if (order == 0) |
| 150 | goto drop; |
| 151 | if (order < 0) { |
| 152 | meta->timestamp = meta1->timestamp; |
| 153 | skb_insert(skb1, skb, &sk->sk_receive_queue); |
| 154 | skb = NULL; |
| 155 | break; |
| 156 | } |
| 157 | } |
| 158 | if (skb) { |
| 159 | meta->timestamp = now; |
| 160 | skb_queue_tail(&sk->sk_receive_queue, skb); |
| 161 | } |
| 162 | |
| 163 | /* Remove packets from receive queue as long as |
| 164 | * 1. the receive buffer is full, |
| 165 | * 2. they are queued longer than one second, or |
| 166 | * 3. there are no missing packets before them. */ |
| 167 | skb_queue_walk_safe(&sk->sk_receive_queue, skb, skb1) { |
| 168 | meta = skb_meta(skb); |
| 169 | if (atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf && |
| 170 | now - meta->timestamp < HZ && |
| 171 | meta->sequence != opt->recv_sequence) |
| 172 | break; |
| 173 | skb_unlink(skb, &sk->sk_receive_queue); |
| 174 | opt->recv_sequence = (__u16)(meta->sequence + 1); |
| 175 | skb_orphan(skb); |
| 176 | ppp_input(&pppox_sk(sk)->chan, skb); |
| 177 | } |
| 178 | return NET_RX_SUCCESS; |
| 179 | } |
| 180 | |
| 181 | /* Flush receive queue if sequencing is disabled. */ |
| 182 | skb_queue_purge(&sk->sk_receive_queue); |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 183 | skb_orphan(skb); |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 184 | ppp_input(&pppox_sk(sk)->chan, skb); |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 185 | return NET_RX_SUCCESS; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 186 | drop: |
| 187 | kfree_skb(skb); |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 188 | return NET_RX_DROP; |
| 189 | } |
| 190 | |
| 191 | static int pppolac_recv(struct sock *sk_udp, struct sk_buff *skb) |
| 192 | { |
| 193 | sock_hold(sk_udp); |
| 194 | sk_receive_skb(sk_udp, skb, 0); |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 195 | return 0; |
| 196 | } |
| 197 | |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 198 | static struct sk_buff_head delivery_queue; |
| 199 | |
| 200 | static void pppolac_xmit_core(struct work_struct *delivery_work) |
| 201 | { |
| 202 | mm_segment_t old_fs = get_fs(); |
| 203 | struct sk_buff *skb; |
| 204 | |
| 205 | set_fs(KERNEL_DS); |
| 206 | while ((skb = skb_dequeue(&delivery_queue))) { |
| 207 | struct sock *sk_udp = skb->sk; |
| 208 | struct kvec iov = {.iov_base = skb->data, .iov_len = skb->len}; |
Subash Abhinov Kasiviswanathan | 149a5c6 | 2017-04-28 12:53:04 -0600 | [diff] [blame^] | 209 | struct msghdr msg = { |
| 210 | .msg_flags = MSG_NOSIGNAL | MSG_DONTWAIT, |
| 211 | }; |
Guenter Roeck | 9079f24 | 2016-03-01 09:44:17 -0800 | [diff] [blame] | 212 | |
| 213 | iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iov, 1, |
| 214 | skb->len); |
Amit Pundir | 85d6388 | 2015-12-08 18:26:39 +0530 | [diff] [blame] | 215 | sk_udp->sk_prot->sendmsg(sk_udp, &msg, skb->len); |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 216 | kfree_skb(skb); |
| 217 | } |
| 218 | set_fs(old_fs); |
| 219 | } |
| 220 | |
| 221 | static DECLARE_WORK(delivery_work, pppolac_xmit_core); |
| 222 | |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 223 | static int pppolac_xmit(struct ppp_channel *chan, struct sk_buff *skb) |
| 224 | { |
| 225 | struct sock *sk_udp = (struct sock *)chan->private; |
| 226 | struct pppolac_opt *opt = &pppox_sk(sk_udp->sk_user_data)->proto.lac; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 227 | |
| 228 | /* Install PPP address and control. */ |
| 229 | skb_push(skb, 2); |
| 230 | skb->data[0] = PPP_ADDR; |
| 231 | skb->data[1] = PPP_CTRL; |
| 232 | |
| 233 | /* Install L2TP header. */ |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 234 | if (atomic_read(&opt->sequencing)) { |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 235 | skb_push(skb, 10); |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 236 | skb->data[0] = L2TP_SEQUENCE_BIT; |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 237 | skb->data[6] = opt->xmit_sequence >> 8; |
| 238 | skb->data[7] = opt->xmit_sequence; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 239 | skb->data[8] = 0; |
| 240 | skb->data[9] = 0; |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 241 | opt->xmit_sequence++; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 242 | } else { |
| 243 | skb_push(skb, 6); |
| 244 | skb->data[0] = 0; |
| 245 | } |
| 246 | skb->data[1] = L2TP_VERSION; |
| 247 | unaligned(&skb->data[2])->u32 = opt->remote; |
| 248 | |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 249 | /* Now send the packet via the delivery queue. */ |
| 250 | skb_set_owner_w(skb, sk_udp); |
| 251 | skb_queue_tail(&delivery_queue, skb); |
| 252 | schedule_work(&delivery_work); |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 253 | return 1; |
| 254 | } |
| 255 | |
| 256 | /******************************************************************************/ |
| 257 | |
| 258 | static struct ppp_channel_ops pppolac_channel_ops = { |
| 259 | .start_xmit = pppolac_xmit, |
| 260 | }; |
| 261 | |
| 262 | static int pppolac_connect(struct socket *sock, struct sockaddr *useraddr, |
| 263 | int addrlen, int flags) |
| 264 | { |
| 265 | struct sock *sk = sock->sk; |
| 266 | struct pppox_sock *po = pppox_sk(sk); |
| 267 | struct sockaddr_pppolac *addr = (struct sockaddr_pppolac *)useraddr; |
| 268 | struct socket *sock_udp = NULL; |
| 269 | struct sock *sk_udp; |
| 270 | int error; |
| 271 | |
| 272 | if (addrlen != sizeof(struct sockaddr_pppolac) || |
| 273 | !addr->local.tunnel || !addr->local.session || |
| 274 | !addr->remote.tunnel || !addr->remote.session) { |
| 275 | return -EINVAL; |
| 276 | } |
| 277 | |
| 278 | lock_sock(sk); |
| 279 | error = -EALREADY; |
| 280 | if (sk->sk_state != PPPOX_NONE) |
| 281 | goto out; |
| 282 | |
| 283 | sock_udp = sockfd_lookup(addr->udp_socket, &error); |
| 284 | if (!sock_udp) |
| 285 | goto out; |
| 286 | sk_udp = sock_udp->sk; |
| 287 | lock_sock(sk_udp); |
| 288 | |
| 289 | /* Remove this check when IPv6 supports UDP encapsulation. */ |
| 290 | error = -EAFNOSUPPORT; |
| 291 | if (sk_udp->sk_family != AF_INET) |
| 292 | goto out; |
| 293 | error = -EPROTONOSUPPORT; |
| 294 | if (sk_udp->sk_protocol != IPPROTO_UDP) |
| 295 | goto out; |
| 296 | error = -EDESTADDRREQ; |
| 297 | if (sk_udp->sk_state != TCP_ESTABLISHED) |
| 298 | goto out; |
| 299 | error = -EBUSY; |
| 300 | if (udp_sk(sk_udp)->encap_type || sk_udp->sk_user_data) |
| 301 | goto out; |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 302 | if (!sk_udp->sk_bound_dev_if) { |
| 303 | struct dst_entry *dst = sk_dst_get(sk_udp); |
| 304 | error = -ENODEV; |
| 305 | if (!dst) |
| 306 | goto out; |
| 307 | sk_udp->sk_bound_dev_if = dst->dev->ifindex; |
| 308 | dst_release(dst); |
| 309 | } |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 310 | |
| 311 | po->chan.hdrlen = 12; |
| 312 | po->chan.private = sk_udp; |
| 313 | po->chan.ops = &pppolac_channel_ops; |
JP Abgrall | bda61e5 | 2012-09-20 16:34:10 -0700 | [diff] [blame] | 314 | po->chan.mtu = PPP_MRU - 80; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 315 | po->proto.lac.local = unaligned(&addr->local)->u32; |
| 316 | po->proto.lac.remote = unaligned(&addr->remote)->u32; |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 317 | atomic_set(&po->proto.lac.sequencing, 1); |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 318 | po->proto.lac.backlog_rcv = sk_udp->sk_backlog_rcv; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 319 | |
| 320 | error = ppp_register_channel(&po->chan); |
| 321 | if (error) |
| 322 | goto out; |
| 323 | |
| 324 | sk->sk_state = PPPOX_CONNECTED; |
| 325 | udp_sk(sk_udp)->encap_type = UDP_ENCAP_L2TPINUDP; |
| 326 | udp_sk(sk_udp)->encap_rcv = pppolac_recv; |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 327 | sk_udp->sk_backlog_rcv = pppolac_recv_core; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 328 | sk_udp->sk_user_data = sk; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 329 | out: |
| 330 | if (sock_udp) { |
| 331 | release_sock(sk_udp); |
| 332 | if (error) |
| 333 | sockfd_put(sock_udp); |
| 334 | } |
| 335 | release_sock(sk); |
| 336 | return error; |
| 337 | } |
| 338 | |
| 339 | static int pppolac_release(struct socket *sock) |
| 340 | { |
| 341 | struct sock *sk = sock->sk; |
| 342 | |
| 343 | if (!sk) |
| 344 | return 0; |
| 345 | |
| 346 | lock_sock(sk); |
| 347 | if (sock_flag(sk, SOCK_DEAD)) { |
| 348 | release_sock(sk); |
| 349 | return -EBADF; |
| 350 | } |
| 351 | |
| 352 | if (sk->sk_state != PPPOX_NONE) { |
| 353 | struct sock *sk_udp = (struct sock *)pppox_sk(sk)->chan.private; |
| 354 | lock_sock(sk_udp); |
Chia-chi Yeh | f6cd375 | 2011-04-15 15:22:09 -0700 | [diff] [blame] | 355 | skb_queue_purge(&sk->sk_receive_queue); |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 356 | pppox_unbind_sock(sk); |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 357 | udp_sk(sk_udp)->encap_type = 0; |
| 358 | udp_sk(sk_udp)->encap_rcv = NULL; |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 359 | sk_udp->sk_backlog_rcv = pppox_sk(sk)->proto.lac.backlog_rcv; |
| 360 | sk_udp->sk_user_data = NULL; |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 361 | release_sock(sk_udp); |
| 362 | sockfd_put(sk_udp->sk_socket); |
| 363 | } |
| 364 | |
| 365 | sock_orphan(sk); |
| 366 | sock->sk = NULL; |
| 367 | release_sock(sk); |
| 368 | sock_put(sk); |
| 369 | return 0; |
| 370 | } |
| 371 | |
| 372 | /******************************************************************************/ |
| 373 | |
| 374 | static struct proto pppolac_proto = { |
| 375 | .name = "PPPOLAC", |
| 376 | .owner = THIS_MODULE, |
| 377 | .obj_size = sizeof(struct pppox_sock), |
| 378 | }; |
| 379 | |
| 380 | static struct proto_ops pppolac_proto_ops = { |
| 381 | .family = PF_PPPOX, |
| 382 | .owner = THIS_MODULE, |
| 383 | .release = pppolac_release, |
| 384 | .bind = sock_no_bind, |
| 385 | .connect = pppolac_connect, |
| 386 | .socketpair = sock_no_socketpair, |
| 387 | .accept = sock_no_accept, |
| 388 | .getname = sock_no_getname, |
| 389 | .poll = sock_no_poll, |
| 390 | .ioctl = pppox_ioctl, |
| 391 | .listen = sock_no_listen, |
| 392 | .shutdown = sock_no_shutdown, |
| 393 | .setsockopt = sock_no_setsockopt, |
| 394 | .getsockopt = sock_no_getsockopt, |
| 395 | .sendmsg = sock_no_sendmsg, |
| 396 | .recvmsg = sock_no_recvmsg, |
| 397 | .mmap = sock_no_mmap, |
| 398 | }; |
| 399 | |
Amit Pundir | a7e707e | 2015-12-08 12:47:01 +0530 | [diff] [blame] | 400 | static int pppolac_create(struct net *net, struct socket *sock, int kern) |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 401 | { |
| 402 | struct sock *sk; |
| 403 | |
Amit Pundir | a7e707e | 2015-12-08 12:47:01 +0530 | [diff] [blame] | 404 | sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppolac_proto, kern); |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 405 | if (!sk) |
| 406 | return -ENOMEM; |
| 407 | |
| 408 | sock_init_data(sock, sk); |
| 409 | sock->state = SS_UNCONNECTED; |
| 410 | sock->ops = &pppolac_proto_ops; |
| 411 | sk->sk_protocol = PX_PROTO_OLAC; |
| 412 | sk->sk_state = PPPOX_NONE; |
| 413 | return 0; |
| 414 | } |
| 415 | |
| 416 | /******************************************************************************/ |
| 417 | |
| 418 | static struct pppox_proto pppolac_pppox_proto = { |
| 419 | .create = pppolac_create, |
| 420 | .owner = THIS_MODULE, |
| 421 | }; |
| 422 | |
| 423 | static int __init pppolac_init(void) |
| 424 | { |
| 425 | int error; |
| 426 | |
| 427 | error = proto_register(&pppolac_proto, 0); |
| 428 | if (error) |
| 429 | return error; |
| 430 | |
| 431 | error = register_pppox_proto(PX_PROTO_OLAC, &pppolac_pppox_proto); |
| 432 | if (error) |
| 433 | proto_unregister(&pppolac_proto); |
Chia-chi Yeh | 32f7ae9 | 2009-06-13 02:29:04 +0800 | [diff] [blame] | 434 | else |
| 435 | skb_queue_head_init(&delivery_queue); |
Chia-chi Yeh | 5ebc1fc | 2009-05-08 04:02:40 +0800 | [diff] [blame] | 436 | return error; |
| 437 | } |
| 438 | |
| 439 | static void __exit pppolac_exit(void) |
| 440 | { |
| 441 | unregister_pppox_proto(PX_PROTO_OLAC); |
| 442 | proto_unregister(&pppolac_proto); |
| 443 | } |
| 444 | |
| 445 | module_init(pppolac_init); |
| 446 | module_exit(pppolac_exit); |
| 447 | |
| 448 | MODULE_DESCRIPTION("PPP on L2TP Access Concentrator (PPPoLAC)"); |
| 449 | MODULE_AUTHOR("Chia-chi Yeh <chiachi@android.com>"); |
| 450 | MODULE_LICENSE("GPL"); |