diff options
Diffstat (limited to 'ANDROID_3.4.5/drivers/net/ppp/pppopns.c')
| -rw-r--r-- | ANDROID_3.4.5/drivers/net/ppp/pppopns.c | 428 |
1 files changed, 0 insertions, 428 deletions
diff --git a/ANDROID_3.4.5/drivers/net/ppp/pppopns.c b/ANDROID_3.4.5/drivers/net/ppp/pppopns.c deleted file mode 100644 index 6016d29c..00000000 --- a/ANDROID_3.4.5/drivers/net/ppp/pppopns.c +++ /dev/null @@ -1,428 +0,0 @@ -/* drivers/net/pppopns.c - * - * Driver for PPP on PPTP Network Server / PPPoPNS Socket (RFC 2637) - * - * Copyright (C) 2009 Google, Inc. - * - * This software is licensed under the terms of the GNU General Public - * License version 2, as published by the Free Software Foundation, and - * may be copied, distributed, and modified under those terms. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - */ - -/* This driver handles PPTP data packets between a RAW socket and a PPP channel. - * The socket is created in the kernel space and connected to the same address - * of the control socket. Outgoing packets are always sent with sequences but - * without acknowledgements. Incoming packets with sequences are reordered - * within a sliding window of one second. Currently reordering only happens when - * a packet is received. It is done for simplicity since no additional locks or - * threads are required. This driver should work on both IPv4 and IPv6. */ - -#include <linux/module.h> -#include <linux/jiffies.h> -#include <linux/workqueue.h> -#include <linux/skbuff.h> -#include <linux/file.h> -#include <linux/netdevice.h> -#include <linux/net.h> -#include <linux/ppp_defs.h> -#include <linux/if.h> -#include <linux/if_ppp.h> -#include <linux/if_pppox.h> -#include <linux/ppp_channel.h> -#include <asm/uaccess.h> - -#define GRE_HEADER_SIZE 8 - -#define PPTP_GRE_BITS htons(0x2001) -#define PPTP_GRE_BITS_MASK htons(0xEF7F) -#define PPTP_GRE_SEQ_BIT htons(0x1000) -#define PPTP_GRE_ACK_BIT htons(0x0080) -#define PPTP_GRE_TYPE htons(0x880B) - -#define PPP_ADDR 0xFF -#define PPP_CTRL 0x03 - -struct header { - __u16 bits; - __u16 type; - __u16 length; - __u16 call; - __u32 sequence; -} __attribute__((packed)); - -struct meta { - __u32 sequence; - __u32 timestamp; -}; - -static inline struct meta *skb_meta(struct sk_buff *skb) -{ - return (struct meta *)skb->cb; -} - -/******************************************************************************/ - -static int pppopns_recv_core(struct sock *sk_raw, struct sk_buff *skb) -{ - struct sock *sk = (struct sock *)sk_raw->sk_user_data; - struct pppopns_opt *opt = &pppox_sk(sk)->proto.pns; - struct meta *meta = skb_meta(skb); - __u32 now = jiffies; - struct header *hdr; - - /* Skip transport header */ - skb_pull(skb, skb_transport_header(skb) - skb->data); - - /* Drop the packet if GRE header is missing. */ - if (skb->len < GRE_HEADER_SIZE) - goto drop; - hdr = (struct header *)skb->data; - - /* Check the header. */ - if (hdr->type != PPTP_GRE_TYPE || hdr->call != opt->local || - (hdr->bits & PPTP_GRE_BITS_MASK) != PPTP_GRE_BITS) - goto drop; - - /* Skip all fields including optional ones. */ - if (!skb_pull(skb, GRE_HEADER_SIZE + - (hdr->bits & PPTP_GRE_SEQ_BIT ? 4 : 0) + - (hdr->bits & PPTP_GRE_ACK_BIT ? 4 : 0))) - goto drop; - - /* Check the length. */ - if (skb->len != ntohs(hdr->length)) - goto drop; - - /* Check the sequence if it is present. */ - if (hdr->bits & PPTP_GRE_SEQ_BIT) { - meta->sequence = ntohl(hdr->sequence); - if ((__s32)(meta->sequence - opt->recv_sequence) < 0) - goto drop; - } - - /* Skip PPP address and control if they are present. */ - if (skb->len >= 2 && skb->data[0] == PPP_ADDR && - skb->data[1] == PPP_CTRL) - skb_pull(skb, 2); - - /* Fix PPP protocol if it is compressed. */ - if (skb->len >= 1 && skb->data[0] & 1) - skb_push(skb, 1)[0] = 0; - - /* Drop the packet if PPP protocol is missing. */ - if (skb->len < 2) - goto drop; - - /* Perform reordering if sequencing is enabled. */ - if (hdr->bits & PPTP_GRE_SEQ_BIT) { - struct sk_buff *skb1; - - /* Insert the packet into receive queue in order. */ - skb_set_owner_r(skb, sk); - skb_queue_walk(&sk->sk_receive_queue, skb1) { - struct meta *meta1 = skb_meta(skb1); - __s32 order = meta->sequence - meta1->sequence; - if (order == 0) - goto drop; - if (order < 0) { - meta->timestamp = meta1->timestamp; - skb_insert(skb1, skb, &sk->sk_receive_queue); - skb = NULL; - break; - } - } - if (skb) { - meta->timestamp = now; - skb_queue_tail(&sk->sk_receive_queue, skb); - } - - /* Remove packets from receive queue as long as - * 1. the receive buffer is full, - * 2. they are queued longer than one second, or - * 3. there are no missing packets before them. */ - skb_queue_walk_safe(&sk->sk_receive_queue, skb, skb1) { - meta = skb_meta(skb); - if (atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf && - now - meta->timestamp < HZ && - meta->sequence != opt->recv_sequence) - break; - skb_unlink(skb, &sk->sk_receive_queue); - opt->recv_sequence = meta->sequence + 1; - skb_orphan(skb); - ppp_input(&pppox_sk(sk)->chan, skb); - } - return NET_RX_SUCCESS; - } - - /* Flush receive queue if sequencing is disabled. */ - skb_queue_purge(&sk->sk_receive_queue); - skb_orphan(skb); - ppp_input(&pppox_sk(sk)->chan, skb); - return NET_RX_SUCCESS; -drop: - kfree_skb(skb); - return NET_RX_DROP; -} - -static void pppopns_recv(struct sock *sk_raw, int length) -{ - struct sk_buff *skb; - while ((skb = skb_dequeue(&sk_raw->sk_receive_queue))) { - sock_hold(sk_raw); - sk_receive_skb(sk_raw, skb, 0); - } -} - -static struct sk_buff_head delivery_queue; - -static void pppopns_xmit_core(struct work_struct *delivery_work) -{ - mm_segment_t old_fs = get_fs(); - struct sk_buff *skb; - - set_fs(KERNEL_DS); - while ((skb = skb_dequeue(&delivery_queue))) { - struct sock *sk_raw = skb->sk; - struct kvec iov = {.iov_base = skb->data, .iov_len = skb->len}; - struct msghdr msg = { - .msg_iov = (struct iovec *)&iov, - .msg_iovlen = 1, - .msg_flags = MSG_NOSIGNAL | MSG_DONTWAIT, - }; - sk_raw->sk_prot->sendmsg(NULL, sk_raw, &msg, skb->len); - kfree_skb(skb); - } - set_fs(old_fs); -} - -static DECLARE_WORK(delivery_work, pppopns_xmit_core); - -static int pppopns_xmit(struct ppp_channel *chan, struct sk_buff *skb) -{ - struct sock *sk_raw = (struct sock *)chan->private; - struct pppopns_opt *opt = &pppox_sk(sk_raw->sk_user_data)->proto.pns; - struct header *hdr; - __u16 length; - - /* Install PPP address and control. */ - skb_push(skb, 2); - skb->data[0] = PPP_ADDR; - skb->data[1] = PPP_CTRL; - length = skb->len; - - /* Install PPTP GRE header. */ - hdr = (struct header *)skb_push(skb, 12); - hdr->bits = PPTP_GRE_BITS | PPTP_GRE_SEQ_BIT; - hdr->type = PPTP_GRE_TYPE; - hdr->length = htons(length); - hdr->call = opt->remote; - hdr->sequence = htonl(opt->xmit_sequence); - opt->xmit_sequence++; - - /* Now send the packet via the delivery queue. */ - skb_set_owner_w(skb, sk_raw); - skb_queue_tail(&delivery_queue, skb); - schedule_work(&delivery_work); - return 1; -} - -/******************************************************************************/ - -static struct ppp_channel_ops pppopns_channel_ops = { - .start_xmit = pppopns_xmit, -}; - -static int pppopns_connect(struct socket *sock, struct sockaddr *useraddr, - int addrlen, int flags) -{ - struct sock *sk = sock->sk; - struct pppox_sock *po = pppox_sk(sk); - struct sockaddr_pppopns *addr = (struct sockaddr_pppopns *)useraddr; - struct sockaddr_storage ss; - struct socket *sock_tcp = NULL; - struct socket *sock_raw = NULL; - struct sock *sk_tcp; - struct sock *sk_raw; - int error; - - if (addrlen != sizeof(struct sockaddr_pppopns)) - return -EINVAL; - - lock_sock(sk); - error = -EALREADY; - if (sk->sk_state != PPPOX_NONE) - goto out; - - sock_tcp = sockfd_lookup(addr->tcp_socket, &error); - if (!sock_tcp) - goto out; - sk_tcp = sock_tcp->sk; - error = -EPROTONOSUPPORT; - if (sk_tcp->sk_protocol != IPPROTO_TCP) - goto out; - addrlen = sizeof(struct sockaddr_storage); - error = kernel_getpeername(sock_tcp, (struct sockaddr *)&ss, &addrlen); - if (error) - goto out; - if (!sk_tcp->sk_bound_dev_if) { - struct dst_entry *dst = sk_dst_get(sk_tcp); - error = -ENODEV; - if (!dst) - goto out; - sk_tcp->sk_bound_dev_if = dst->dev->ifindex; - dst_release(dst); - } - - error = sock_create(ss.ss_family, SOCK_RAW, IPPROTO_GRE, &sock_raw); - if (error) - goto out; - sk_raw = sock_raw->sk; - sk_raw->sk_bound_dev_if = sk_tcp->sk_bound_dev_if; - error = kernel_connect(sock_raw, (struct sockaddr *)&ss, addrlen, 0); - if (error) - goto out; - - po->chan.hdrlen = 14; - po->chan.private = sk_raw; - po->chan.ops = &pppopns_channel_ops; - po->chan.mtu = PPP_MRU - 80; - po->proto.pns.local = addr->local; - po->proto.pns.remote = addr->remote; - po->proto.pns.data_ready = sk_raw->sk_data_ready; - po->proto.pns.backlog_rcv = sk_raw->sk_backlog_rcv; - - error = ppp_register_channel(&po->chan); - if (error) - goto out; - - sk->sk_state = PPPOX_CONNECTED; - lock_sock(sk_raw); - sk_raw->sk_data_ready = pppopns_recv; - sk_raw->sk_backlog_rcv = pppopns_recv_core; - sk_raw->sk_user_data = sk; - release_sock(sk_raw); -out: - if (sock_tcp) - sockfd_put(sock_tcp); - if (error && sock_raw) - sock_release(sock_raw); - release_sock(sk); - return error; -} - -static int pppopns_release(struct socket *sock) -{ - struct sock *sk = sock->sk; - - if (!sk) - return 0; - - lock_sock(sk); - if (sock_flag(sk, SOCK_DEAD)) { - release_sock(sk); - return -EBADF; - } - - if (sk->sk_state != PPPOX_NONE) { - struct sock *sk_raw = (struct sock *)pppox_sk(sk)->chan.private; - lock_sock(sk_raw); - skb_queue_purge(&sk->sk_receive_queue); - pppox_unbind_sock(sk); - sk_raw->sk_data_ready = pppox_sk(sk)->proto.pns.data_ready; - sk_raw->sk_backlog_rcv = pppox_sk(sk)->proto.pns.backlog_rcv; - sk_raw->sk_user_data = NULL; - release_sock(sk_raw); - sock_release(sk_raw->sk_socket); - } - - sock_orphan(sk); - sock->sk = NULL; - release_sock(sk); - sock_put(sk); - return 0; -} - -/******************************************************************************/ - -static struct proto pppopns_proto = { - .name = "PPPOPNS", - .owner = THIS_MODULE, - .obj_size = sizeof(struct pppox_sock), -}; - -static struct proto_ops pppopns_proto_ops = { - .family = PF_PPPOX, - .owner = THIS_MODULE, - .release = pppopns_release, - .bind = sock_no_bind, - .connect = pppopns_connect, - .socketpair = sock_no_socketpair, - .accept = sock_no_accept, - .getname = sock_no_getname, - .poll = sock_no_poll, - .ioctl = pppox_ioctl, - .listen = sock_no_listen, - .shutdown = sock_no_shutdown, - .setsockopt = sock_no_setsockopt, - .getsockopt = sock_no_getsockopt, - .sendmsg = sock_no_sendmsg, - .recvmsg = sock_no_recvmsg, - .mmap = sock_no_mmap, -}; - -static int pppopns_create(struct net *net, struct socket *sock) -{ - struct sock *sk; - - sk = sk_alloc(net, PF_PPPOX, GFP_KERNEL, &pppopns_proto); - if (!sk) - return -ENOMEM; - - sock_init_data(sock, sk); - sock->state = SS_UNCONNECTED; - sock->ops = &pppopns_proto_ops; - sk->sk_protocol = PX_PROTO_OPNS; - sk->sk_state = PPPOX_NONE; - return 0; -} - -/******************************************************************************/ - -static struct pppox_proto pppopns_pppox_proto = { - .create = pppopns_create, - .owner = THIS_MODULE, -}; - -static int __init pppopns_init(void) -{ - int error; - - error = proto_register(&pppopns_proto, 0); - if (error) - return error; - - error = register_pppox_proto(PX_PROTO_OPNS, &pppopns_pppox_proto); - if (error) - proto_unregister(&pppopns_proto); - else - skb_queue_head_init(&delivery_queue); - return error; -} - -static void __exit pppopns_exit(void) -{ - unregister_pppox_proto(PX_PROTO_OPNS); - proto_unregister(&pppopns_proto); -} - -module_init(pppopns_init); -module_exit(pppopns_exit); - -MODULE_DESCRIPTION("PPP on PPTP Network Server (PPPoPNS)"); -MODULE_AUTHOR("Chia-chi Yeh <chiachi@android.com>"); -MODULE_LICENSE("GPL"); |