* Driver for PPP on L2TP Access Concentrator / PPPoLAC Socket (RFC 2661)
*
* Copyright (C) 2009 Google, Inc.
+ * Author: Chia-chi Yeh <chiachi@android.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* only works on IPv4 due to the lack of UDP encapsulation support in IPv6. */
#include <linux/module.h>
-#include <linux/workqueue.h>
#include <linux/skbuff.h>
#include <linux/file.h>
-#include <linux/netdevice.h>
#include <linux/net.h>
#include <linux/udp.h>
#include <linux/ppp_defs.h>
#include <linux/if_pppox.h>
#include <linux/ppp_channel.h>
#include <net/tcp_states.h>
-#include <asm/uaccess.h>
-#define L2TP_CONTROL_BIT 0x80
-#define L2TP_LENGTH_BIT 0x40
-#define L2TP_SEQUENCE_BIT 0x08
-#define L2TP_OFFSET_BIT 0x02
-#define L2TP_VERSION 0x02
+#define L2TP_CONTROL_MASK 0x80
#define L2TP_VERSION_MASK 0x0F
+#define L2TP_VERSION 0x02
+#define L2TP_LENGTH_MASK 0x40
+#define L2TP_OFFSET_MASK 0x02
+#define L2TP_SEQUENCE_MASK 0x08
#define PPP_ADDR 0xFF
#define PPP_CTRL 0x03
return (union unaligned *)ptr;
}
-static int pppolac_recv_core(struct sock *sk_udp, struct sk_buff *skb)
+static int pppolac_recv(struct sock *sk_udp, struct sk_buff *skb)
{
- struct sock *sk = (struct sock *)sk_udp->sk_user_data;
- struct pppolac_opt *opt = &pppox_sk(sk)->proto.lac;
+ struct sock *sk;
+ struct pppolac_opt *opt;
__u8 bits;
__u8 *ptr;
goto drop;
/* Put it back if it is a control packet. */
- if (skb->data[sizeof(struct udphdr)] & L2TP_CONTROL_BIT)
- return opt->backlog_rcv(sk_udp, skb);
+ if (skb->data[sizeof(struct udphdr)] & L2TP_CONTROL_MASK)
+ return 1;
- /* Skip UDP header. */
+ /* Now the packet is ours. Skip UDP header. */
skb_pull(skb, sizeof(struct udphdr));
/* Check the version. */
ptr = &skb->data[2];
/* Check the length if it is present. */
- if (bits & L2TP_LENGTH_BIT) {
+ if (bits & L2TP_LENGTH_MASK) {
if ((ptr[0] << 8 | ptr[1]) != skb->len)
goto drop;
ptr += 2;
}
/* Skip all fields including optional ones. */
- if (!skb_pull(skb, 6 + (bits & L2TP_SEQUENCE_BIT ? 4 : 0) +
- (bits & L2TP_LENGTH_BIT ? 2 : 0) +
- (bits & L2TP_OFFSET_BIT ? 2 : 0)))
+ if (!skb_pull(skb, 6 + (bits & L2TP_SEQUENCE_MASK ? 4 : 0) +
+ (bits & L2TP_LENGTH_MASK ? 2 : 0) +
+ (bits & L2TP_OFFSET_MASK ? 2 : 0)))
goto drop;
/* Skip the offset padding if it is present. */
- if (bits & L2TP_OFFSET_BIT &&
+ if (bits & L2TP_OFFSET_MASK &&
!skb_pull(skb, skb->data[-2] << 8 | skb->data[-1]))
goto drop;
+ /* Now ptr is pointing to the tunnel and skb is pointing to the payload.
+ * We have to lock sk_udp to prevent sk from being closed. */
+ lock_sock(sk_udp);
+ sk = sk_udp->sk_user_data;
+ if (!sk) {
+ release_sock(sk_udp);
+ goto drop;
+ }
+ sock_hold(sk);
+ release_sock(sk_udp);
+ opt = &pppox_sk(sk)->proto.lac;
+
/* Check the tunnel and the session. */
- if (unaligned(ptr)->u32 != opt->local)
+ if (unaligned(ptr)->u32 != opt->local) {
+ sock_put(sk);
goto drop;
+ }
- /* Check the sequence if it is present. According to RFC 2661 section
- * 5.4, the only thing to do is to update opt->sequencing. */
- opt->sequencing = bits & L2TP_SEQUENCE_BIT;
+ /* Check the sequence if it is present. According to RFC 2661 page 10
+ * and 43, the only thing to do is updating opt->sequencing. */
+ opt->sequencing = bits & L2TP_SEQUENCE_MASK;
/* Skip PPP address and control if they are present. */
if (skb->len >= 2 && skb->data[0] == PPP_ADDR &&
if (skb->len >= 1 && skb->data[0] & 1)
skb_push(skb, 1)[0] = 0;
- /* Finally, deliver the packet to PPP channel. */
+ /* Finally, deliver the packet to PPP channel. We have to lock sk to
+ * prevent another thread from calling pppox_unbind_sock(). */
skb_orphan(skb);
+ lock_sock(sk);
ppp_input(&pppox_sk(sk)->chan, skb);
- return NET_RX_SUCCESS;
+ release_sock(sk);
+ sock_put(sk);
+ return 0;
+
drop:
kfree_skb(skb);
- return NET_RX_DROP;
-}
-
-static int pppolac_recv(struct sock *sk_udp, struct sk_buff *skb)
-{
- sock_hold(sk_udp);
- sk_receive_skb(sk_udp, skb, 0);
return 0;
}
-static struct sk_buff_head delivery_queue;
-
-static void pppolac_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_udp = 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_udp->sk_prot->sendmsg(NULL, sk_udp, &msg, skb->len);
- kfree_skb(skb);
- }
- set_fs(old_fs);
-}
-
-static DECLARE_WORK(delivery_work, pppolac_xmit_core);
-
static int pppolac_xmit(struct ppp_channel *chan, struct sk_buff *skb)
{
struct sock *sk_udp = (struct sock *)chan->private;
struct pppolac_opt *opt = &pppox_sk(sk_udp->sk_user_data)->proto.lac;
+ struct msghdr msg = {.msg_flags = MSG_NOSIGNAL | MSG_DONTWAIT};
+ struct kvec iov;
/* Install PPP address and control. */
skb_push(skb, 2);
/* Install L2TP header. */
if (opt->sequencing) {
skb_push(skb, 10);
- skb->data[0] = L2TP_SEQUENCE_BIT;
+ skb->data[0] = L2TP_SEQUENCE_MASK;
skb->data[6] = opt->sequence >> 8;
skb->data[7] = opt->sequence;
skb->data[8] = 0;
skb->data[1] = L2TP_VERSION;
unaligned(&skb->data[2])->u32 = opt->remote;
- /* Now send the packet via the delivery queue. */
- skb_set_owner_w(skb, sk_udp);
- skb_queue_tail(&delivery_queue, skb);
- schedule_work(&delivery_work);
+ /* Now send the packet via UDP socket. */
+ iov.iov_base = skb->data;
+ iov.iov_len = skb->len;
+ kernel_sendmsg(sk_udp->sk_socket, &msg, &iov, 1, skb->len);
+ kfree_skb(skb);
return 1;
}
error = -EBUSY;
if (udp_sk(sk_udp)->encap_type || sk_udp->sk_user_data)
goto out;
- if (!sk_udp->sk_bound_dev_if) {
- struct dst_entry *dst = sk_dst_get(sk_udp);
- error = -ENODEV;
- if (!dst)
- goto out;
- sk_udp->sk_bound_dev_if = dst->dev->ifindex;
- dst_release(dst);
- }
po->chan.hdrlen = 12;
po->chan.private = sk_udp;
po->chan.mtu = PPP_MTU - 80;
po->proto.lac.local = unaligned(&addr->local)->u32;
po->proto.lac.remote = unaligned(&addr->remote)->u32;
- po->proto.lac.backlog_rcv = sk_udp->sk_backlog_rcv;
error = ppp_register_channel(&po->chan);
if (error)
sk->sk_state = PPPOX_CONNECTED;
udp_sk(sk_udp)->encap_type = UDP_ENCAP_L2TPINUDP;
udp_sk(sk_udp)->encap_rcv = pppolac_recv;
- sk_udp->sk_backlog_rcv = pppolac_recv_core;
sk_udp->sk_user_data = sk;
+
out:
if (sock_udp) {
release_sock(sk_udp);
if (sk->sk_state != PPPOX_NONE) {
struct sock *sk_udp = (struct sock *)pppox_sk(sk)->chan.private;
lock_sock(sk_udp);
+
pppox_unbind_sock(sk);
+ sk_udp->sk_user_data = NULL;
udp_sk(sk_udp)->encap_type = 0;
udp_sk(sk_udp)->encap_rcv = NULL;
- sk_udp->sk_backlog_rcv = pppox_sk(sk)->proto.lac.backlog_rcv;
- sk_udp->sk_user_data = NULL;
+
release_sock(sk_udp);
sockfd_put(sk_udp->sk_socket);
}
error = register_pppox_proto(PX_PROTO_OLAC, &pppolac_pppox_proto);
if (error)
proto_unregister(&pppolac_proto);
- else
- skb_queue_head_init(&delivery_queue);
return error;
}
* Driver for PPP on PPTP Network Server / PPPoPNS Socket (RFC 2637)
*
* Copyright (C) 2009 Google, Inc.
+ * Author: Chia-chi Yeh <chiachi@android.com>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* and IPv6. */
#include <linux/module.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_MASK htons(0x2001)
+#define PPTP_GRE_SEQ_MASK htons(0x1000)
+#define PPTP_GRE_ACK_MASK htons(0x0080)
#define PPTP_GRE_TYPE htons(0x880B)
#define PPP_ADDR 0xFF
__u32 sequence;
} __attribute__((packed));
-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 header *hdr;
-
- /* Skip transport header */
- skb_pull(skb, skb_transport_header(skb) - skb->data);
-
- /* Drop the packet if it is too short. */
- if (skb->len < GRE_HEADER_SIZE)
- goto drop;
-
- /* Check the header. */
- hdr = (struct header *)skb->data;
- 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;
-
- /* 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;
-
- /* Finally, deliver the packet to PPP channel. */
- 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 sock *sk;
+ struct pppopns_opt *opt;
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;
+ struct header *hdr;
-static void pppopns_xmit_core(struct work_struct *delivery_work)
-{
- mm_segment_t old_fs = get_fs();
- struct sk_buff *skb;
+ /* Lock sk_raw to prevent sk from being closed. */
+ lock_sock(sk_raw);
+ sk = (struct sock *)sk_raw->sk_user_data;
+ if (!sk) {
+ release_sock(sk_raw);
+ return;
+ }
+ sock_hold(sk);
+ release_sock(sk_raw);
+ opt = &pppox_sk(sk)->proto.pns;
- 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);
+ /* Process packets from the receive queue. */
+ while ((skb = skb_dequeue(&sk_raw->sk_receive_queue))) {
+ skb_pull(skb, skb_transport_header(skb) - skb->data);
+
+ /* Drop the packet if it is too short. */
+ if (skb->len < GRE_HEADER_SIZE)
+ goto drop;
+
+ /* Check the header. */
+ hdr = (struct header *)skb->data;
+ if (hdr->type != PPTP_GRE_TYPE || hdr->call != opt->local ||
+ (hdr->bits & PPTP_GRE_MASK) != PPTP_GRE_MASK)
+ goto drop;
+
+ /* Skip all fields including optional ones. */
+ if (!skb_pull(skb, GRE_HEADER_SIZE +
+ (hdr->bits & PPTP_GRE_SEQ_MASK ? 4 : 0) +
+ (hdr->bits & PPTP_GRE_ACK_MASK ? 4 : 0)))
+ goto drop;
+
+ /* Check the length. */
+ if (skb->len != ntohs(hdr->length))
+ 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;
+
+ /* Deliver the packet to PPP channel. We have to lock sk to
+ * prevent another thread from calling pppox_unbind_sock(). */
+ skb_orphan(skb);
+ lock_sock(sk);
+ ppp_input(&pppox_sk(sk)->chan, skb);
+ release_sock(sk);
+ continue;
+drop:
kfree_skb(skb);
}
- set_fs(old_fs);
+ sock_put(sk);
}
-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 msghdr msg = {.msg_flags = MSG_NOSIGNAL | MSG_DONTWAIT};
+ struct kvec iov;
struct header *hdr;
__u16 length;
/* Install PPTP GRE header. */
hdr = (struct header *)skb_push(skb, 12);
- hdr->bits = PPTP_GRE_BITS | PPTP_GRE_SEQ_BIT;
+ hdr->bits = PPTP_GRE_MASK | PPTP_GRE_SEQ_MASK;
hdr->type = PPTP_GRE_TYPE;
hdr->length = htons(length);
hdr->call = opt->remote;
hdr->sequence = htonl(opt->sequence);
opt->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);
+ /* Now send the packet via RAW socket. */
+ iov.iov_base = skb->data;
+ iov.iov_len = skb->len;
+ kernel_sendmsg(sk_raw->sk_socket, &msg, &iov, 1, skb->len);
+ kfree_skb(skb);
return 1;
}
struct sockaddr_storage ss;
struct socket *sock_tcp = NULL;
struct socket *sock_raw = NULL;
- struct sock *sk_tcp;
struct sock *sk_raw;
int error;
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)
+ if (sock_tcp->sk->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;
+ sk_raw = sock_raw->sk;
po->chan.hdrlen = 14;
po->chan.private = sk_raw;
po->chan.mtu = PPP_MTU - 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);
+ sk_raw->sk_data_ready = pppopns_recv;
+
out:
if (sock_tcp)
sockfd_put(sock_tcp);
struct sock *sk_raw = (struct sock *)pppox_sk(sk)->chan.private;
lock_sock(sk_raw);
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);
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;
}
projects / firefly-linux-kernel-4.4.55.git / commitdiff