Message ID | E1Olbcq-0006hZ-00.xeb-mail-ru@f272.mail.ru |
---|---|
State | Changes Requested, archived |
Delegated to: | David Miller |
Headers | show |
Le mercredi 18 août 2010 à 09:55 +0400, Dmitry Kozlov a écrit : > This patch contains: > 1. pptp driver > 2. gre demultiplexer driver for demultiplexing gre packets with different gre version so > ip_gre and pptp may coexists > 3. ip_gre modification > 4. other stuff > > -- Hi Dmitry I added some comments in your patch. Plus, could you please run scripts/checkpatch.pl on it to correct some style issues ? > MAINTAINERS | 14 + > drivers/net/Kconfig | 11 + > drivers/net/Makefile | 1 + > drivers/net/pptp.c | 747 ++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/if_pppox.h | 20 ++- > include/net/gre.h | 18 ++ > net/ipv4/Kconfig | 7 + > net/ipv4/Makefile | 1 + > net/ipv4/gre.c | 147 +++++++++ > net/ipv4/ip_gre.c | 10 +- > 10 files changed, 970 insertions(+), 6 deletions(-) > > diff --git a/MAINTAINERS b/MAINTAINERS > index 02f75fc..191d7c4 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -6450,6 +6450,20 @@ M: "Maciej W. Rozycki" <macro@linux-mips.org> > S: Maintained > F: drivers/serial/zs.* > > +GRE DEMULTIPLEXER DRIVER > +M: Dmitry Kozlov <D.Kozlov@protek-vrn.ru> > +L: netdev@vger.kernel.org > +S: Maintained > +F: net/ipv4/gre.c > +F: include/net/gre.h > + > +PPTP DRIVER > +M: Dmitry Kozlov <D.Kozlov@protek-vrn.ru> > +L: netdev@vger.kernel.org > +S: Maintained > +F: drivers/net/pptp.c > +W: http://sourceforge.net/projects/accel-pptp > + > THE REST > M: Linus Torvalds <torvalds@linux-foundation.org> > L: linux-kernel@vger.kernel.org > diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig > index ce2fcdd..2fa0516 100644 > --- a/drivers/net/Kconfig > +++ b/drivers/net/Kconfig > @@ -3167,6 +3167,17 @@ config PPPOE > which contains instruction on how to use this driver (under > the heading "Kernel mode PPPoE"). > > +config PPTP > + tristate "PPP over IPv4 (PPTP) (EXPERIMENTAL)" > + depends on EXPERIMENTAL && PPP && NET_IPGRE_DEMUX > + help > + Support for PPP over IPv4.(Point-to-Point Tunneling Protocol) > + > + This driver requires pppd plugin to work in client mode or > + modified pptpd (poptop) to work in server mode. > + See http://accel-pptp.sourceforge.net/ for information how to > + utilize this module. > + > config PPPOATM > tristate "PPP over ATM" > depends on ATM && PPP > diff --git a/drivers/net/Makefile b/drivers/net/Makefile > index 0a0512a..b33fef1 100644 > --- a/drivers/net/Makefile > +++ b/drivers/net/Makefile > @@ -162,6 +162,7 @@ obj-$(CONFIG_PPP_BSDCOMP) += bsd_comp.o > obj-$(CONFIG_PPP_MPPE) += ppp_mppe.o > obj-$(CONFIG_PPPOE) += pppox.o pppoe.o > obj-$(CONFIG_PPPOL2TP) += pppox.o > +obj-$(CONFIG_PPTP) += pppox.o pptp.o > > obj-$(CONFIG_SLIP) += slip.o > obj-$(CONFIG_SLHC) += slhc.o > diff --git a/drivers/net/pptp.c b/drivers/net/pptp.c > new file mode 100644 > index 0000000..5dad2f0 > --- /dev/null > +++ b/drivers/net/pptp.c > @@ -0,0 +1,747 @@ > +/* > + * Point-to-Point Tunneling Protocol for Linux > + * > + * Authors: Dmitry Kozlov <xeb@mail.ru> > + * > + * 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/string.h> > +#include <linux/module.h> > +#include <linux/kernel.h> > +#include <linux/slab.h> > +#include <linux/errno.h> > +#include <linux/netdevice.h> > +#include <linux/net.h> > +#include <linux/skbuff.h> > +#include <linux/init.h> > +#include <linux/ppp_channel.h> > +#include <linux/ppp_defs.h> > +#include <linux/if_pppox.h> > +#include <linux/if_ppp.h> > +#include <linux/notifier.h> > +#include <linux/file.h> > +#include <linux/in.h> > +#include <linux/ip.h> > +#include <linux/netfilter.h> > +#include <linux/netfilter_ipv4.h> > +#include <linux/version.h> > +//#include <linux/spinlock.h> just delete this line > +#include <linux/rcupdate.h> > +#include <linux/semaphore.h> > + > + > +#include <net/sock.h> > +#include <net/protocol.h> > +#include <net/ip.h> > +#include <net/icmp.h> > +#include <net/route.h> > +#include <net/gre.h> > + > +#include <asm/uaccess.h> > + > +#define PPTP_DRIVER_VERSION "0.8.4" > + > +#define MAX_CALLID 65535 > +#define PPP_LCP_ECHOREQ 0x09 > +#define PPP_LCP_ECHOREP 0x0A > +#define SC_RCV_BITS (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP) > + > +static unsigned long *callid_bitmap = NULL; Check DECLARE_BITMAP(). I think it is ok in 2010 to add 8192 bytes of bss in a module, considering typical kernels already use 10 Mbytes of bss. > +static struct pppox_sock **callid_sock=NULL; No need for the "=NULL" > + > + > +static DECLARE_MUTEX(chan_lock); Hmm... semaphores are deprecated, please use a mutex static DEFINE_MUTEX(chan_lock); (check drivers/net/ppp_generic.c for example) > + > +static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb); > +static int pptp_ppp_ioctl(struct ppp_channel *chan, unsigned int cmd, > + unsigned long arg); > +static int pptp_rcv_core(struct sock *sk,struct sk_buff *skb); > + > +static struct ppp_channel_ops pptp_chan_ops = { static const ? > + .start_xmit = pptp_xmit, > + .ioctl = pptp_ppp_ioctl, > +}; > + > + > +#define MISSING_WINDOW 20 > +#define WRAPPED( curseq, lastseq) \ > + ((((curseq) & 0xffffff00) == 0) && \ > + (((lastseq) & 0xffffff00 ) == 0xffffff00)) > + > +/* gre header structure: -------------------------------------------- */ > + > +#define PPTP_GRE_PROTO 0x880B > +#define PPTP_GRE_VER 0x1 > + > +#define PPTP_GRE_FLAG_C 0x80 > +#define PPTP_GRE_FLAG_R 0x40 > +#define PPTP_GRE_FLAG_K 0x20 > +#define PPTP_GRE_FLAG_S 0x10 > +#define PPTP_GRE_FLAG_A 0x80 > + > +#define PPTP_GRE_IS_C(f) ((f)&PPTP_GRE_FLAG_C) > +#define PPTP_GRE_IS_R(f) ((f)&PPTP_GRE_FLAG_R) > +#define PPTP_GRE_IS_K(f) ((f)&PPTP_GRE_FLAG_K) > +#define PPTP_GRE_IS_S(f) ((f)&PPTP_GRE_FLAG_S) > +#define PPTP_GRE_IS_A(f) ((f)&PPTP_GRE_FLAG_A) > + > +#define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header)) > +struct pptp_gre_header { > + u8 flags; /* bitfield */ > + u8 ver; /* should be PPTP_GRE_VER (enhanced GRE) */ > + u16 protocol; /* should be PPTP_GRE_PROTO (ppp-encaps) */ > + u16 payload_len; /* size of ppp payload, not inc. gre header */ > + u16 call_id; /* peer's call_id for this session */ > + u32 seq; /* sequence number. Present if S==1 */ > + u32 ack; /* seq number of highest packet recieved by */ > + /* sender in this session */ > +}; > + > +static struct pppox_sock * lookup_chan(__u16 call_id, __be32 s_addr) > +{ > + struct pppox_sock *sock; > + struct pptp_opt *opt; > + > + rcu_read_lock(); > + sock = rcu_dereference(callid_sock[call_id]); > + if (sock) { > + opt = &sock->proto.pptp; > + if (opt->dst_addr.sin_addr.s_addr != s_addr) sock = NULL; > + else sock_hold(sk_pppox(sock)); > + } > + rcu_read_unlock(); > + > + return sock; > +} > + > +static int lookup_chan_dst(__u16 call_id, __be32 d_addr) > +{ > + struct pppox_sock *sock; > + struct pptp_opt *opt; > + int i; > + > + down(&chan_lock); mutex_lock(&chan_lock) ? > + for(i = find_next_bit(callid_bitmap,MAX_CALLID,1); i < MAX_CALLID; i = find_next_bit(callid_bitmap,MAX_CALLID,i+1)) { > + sock = callid_sock[i]; > + opt = &sock->proto.pptp; > + if (opt->dst_addr.call_id == call_id && opt->dst_addr.sin_addr.s_addr == d_addr) break; > + } > + up(&chan_lock); mutex_unlock() > + > + return i < MAX_CALLID; > +} > + > +static int add_chan(struct pppox_sock *sock) > +{ > + static int call_id = 0; > + int res = -1; > + > + synchronize_rcu(); > + Why is this synchronize_rcu() necessary ? > + down(&chan_lock); > + if (!sock->proto.pptp.src_addr.call_id) { > + call_id = find_next_zero_bit(callid_bitmap,MAX_CALLID,call_id+1); > + if (call_id == MAX_CALLID) > + call_id = find_next_zero_bit(callid_bitmap,MAX_CALLID,1); > + sock->proto.pptp.src_addr.call_id = call_id; > + } else if (test_bit(sock->proto.pptp.src_addr.call_id,callid_bitmap)) > + goto exit; > + > + set_bit(sock->proto.pptp.src_addr.call_id,callid_bitmap); > + rcu_assign_pointer(callid_sock[sock->proto.pptp.src_addr.call_id],sock); > + res = 0; > + > +exit: > + up(&chan_lock); > + > + return res; > +} > + > +static void del_chan(struct pppox_sock *sock) > +{ > + synchronize_rcu(); Are you sure it is at the right place ? > + > + down(&chan_lock); > + clear_bit(sock->proto.pptp.src_addr.call_id,callid_bitmap); > + rcu_assign_pointer(callid_sock[sock->proto.pptp.src_addr.call_id],NULL); > + up(&chan_lock); > +} > + > +static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb) > +{ > + struct sock *sk = (struct sock *) chan->private; > + struct pppox_sock *po = pppox_sk(sk); > + struct pptp_opt *opt = &po->proto.pptp; > + struct pptp_gre_header *hdr; > + unsigned int header_len = sizeof(*hdr); > + int err = 0; > + int islcp; > + int len; > + unsigned char *data; > + __u32 seq_recv; > + > + > + struct rtable *rt; /* Route to the other host */ > + struct net_device *tdev; /* Device to other host */ > + struct iphdr *iph; /* Our new IP header */ > + int max_headroom; /* The extra header space needed */ > + > + if (sk_pppox(po)->sk_state & PPPOX_DEAD) > + goto tx_error; > + > + { > + struct flowi fl = { .oif = 0, > + .nl_u = { .ip4_u = > + { .daddr = opt->dst_addr.sin_addr.s_addr, > + .saddr = opt->src_addr.sin_addr.s_addr, > + .tos = RT_TOS(0) } }, > + .proto = IPPROTO_GRE }; > + if ((err=ip_route_output_key(&init_net,&rt, &fl))) { > + goto tx_error; > + } > + } > + tdev = rt->u.dst.dev; > + > + max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(*iph)+sizeof(*hdr)+2; > + > + if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) { > + struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); > + if (!new_skb) { > + ip_rt_put(rt); > + goto tx_error; > + } > + if (skb->sk) > + skb_set_owner_w(new_skb, skb->sk); > + kfree_skb(skb); > + skb = new_skb; > + } > + > + data = skb->data; > + islcp = ((data[0] << 8) + data[1])== PPP_LCP && 1 <= data[2] && data[2] <= 7; > + > + /* compress protocol field */ > + if ((opt->ppp_flags & SC_COMP_PROT) && data[0] == 0 && !islcp) > + skb_pull(skb,1); > + > + /* > + * Put in the address/control bytes if necessary > + */ bad indent ? Also, dont use 3 lines for small comments : /* Put in the address/control bytes if necessary */ > + if ((opt->ppp_flags & SC_COMP_AC) == 0 || islcp) { > + data = skb_push(skb,2); > + data[0] = PPP_ALLSTATIONS; > + data[1] = PPP_UI; > + } > + > + len = skb->len; > + > + seq_recv = opt->seq_recv; > + > + if (opt->ack_sent == seq_recv) header_len -= sizeof(hdr->ack); > + > + // Push down and install GRE header > + skb_push(skb,header_len); > + hdr = (struct pptp_gre_header *)(skb->data); > + > + hdr->flags = PPTP_GRE_FLAG_K; > + hdr->ver = PPTP_GRE_VER; > + hdr->protocol = htons(PPTP_GRE_PROTO); > + hdr->call_id = htons(opt->dst_addr.call_id); > + > + hdr->flags |= PPTP_GRE_FLAG_S; > + hdr->seq = htonl(++opt->seq_sent); > + if (opt->ack_sent != seq_recv) { > + /* send ack with this message */ > + hdr->ver |= PPTP_GRE_FLAG_A; > + hdr->ack = htonl(seq_recv); > + opt->ack_sent = seq_recv; > + } > + hdr->payload_len = htons(len); > + > + /* > + * Push down and install the IP header. > + */ ditto , one line is ok > + > + skb_reset_transport_header(skb); > + skb_push(skb, sizeof(*iph)); > + skb_reset_network_header(skb); > + memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); > + IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | IPSKB_REROUTED); > + > + iph = ip_hdr(skb); > + iph->version = 4; > + iph->ihl = sizeof(struct iphdr) >> 2; > + if (ip_dont_fragment(sk, &rt->u.dst)) > + iph->frag_off = htons(IP_DF); > + else > + iph->frag_off = 0; > + iph->protocol = IPPROTO_GRE; > + iph->tos = 0; > + iph->daddr = rt->rt_dst; > + iph->saddr = rt->rt_src; > + iph->ttl = dst_metric(&rt->u.dst, RTAX_HOPLIMIT); > + iph->tot_len = htons(skb->len); > + > + skb_dst_drop(skb); > + skb_dst_set(skb,&rt->u.dst); > + > + nf_reset(skb); > + > + skb->ip_summed = CHECKSUM_NONE; > + ip_select_ident(iph, &rt->u.dst, NULL); > + ip_send_check(iph); > + > + ip_local_out(skb); > + > +tx_error: > + return 1; > +} > + > +static int pptp_rcv_core(struct sock *sk,struct sk_buff *skb) > +{ > + struct pppox_sock *po = pppox_sk(sk); > + struct pptp_opt *opt = &po->proto.pptp; > + int headersize,payload_len,seq; > + __u8 *payload; > + struct pptp_gre_header *header; > + > + if (!(sk->sk_state & PPPOX_CONNECTED)) { > + if (sock_queue_rcv_skb(sk, skb)) > + goto drop; > + return NET_RX_SUCCESS; > + } > + > + header = (struct pptp_gre_header *)(skb->data); > + > + /* test if acknowledgement present */ > + if (PPTP_GRE_IS_A(header->ver)) { > + __u32 ack = (PPTP_GRE_IS_S(header->flags))? > + header->ack:header->seq; /* ack in different place if S = 0 */ > + > + ack = ntohl( ack); > + > + if (ack > opt->ack_recv) opt->ack_recv = ack; > + /* also handle sequence number wrap-around */ > + if (WRAPPED(ack,opt->ack_recv)) opt->ack_recv = ack; > + } > + > + /* test if payload present */ > + if (!PPTP_GRE_IS_S(header->flags)) { > + goto drop; > + } > + > + headersize = sizeof(*header); > + payload_len = ntohs(header->payload_len); > + seq = ntohl(header->seq); > + > + /* no ack present? */ > + if (!PPTP_GRE_IS_A(header->ver)) headersize -= sizeof(header->ack); > + /* check for incomplete packet (length smaller than expected) */ > + if (skb->len - headersize < payload_len) { > + goto drop; > + } > + > + payload = skb->data+headersize; > + /* check for expected sequence number */ > + if ( seq < opt->seq_recv + 1 || WRAPPED(opt->seq_recv, seq) ) { > + if ( (payload[0] == PPP_ALLSTATIONS) && (payload[1] == PPP_UI) && > + (PPP_PROTOCOL(payload) == PPP_LCP) && > + ((payload[4] == PPP_LCP_ECHOREQ) || (payload[4] == PPP_LCP_ECHOREP)) ) { > + goto allow_packet; > + } > + }else{ > + opt->seq_recv = seq; > +allow_packet: > + skb_pull(skb,headersize); > + > + if (payload[0] == PPP_ALLSTATIONS && payload[1] == PPP_UI) { > + /* chop off address/control */ > + if (skb->len < 3) > + goto drop; > + skb_pull(skb,2); > + } > + > + if ((*skb->data) & 1) { > + /* protocol is compressed */ > + skb_push(skb, 1)[0] = 0; > + } > + > + skb->ip_summed = CHECKSUM_NONE; > + skb_set_network_header(skb,skb->head-skb->data); > + ppp_input(&po->chan,skb); > + > + return NET_RX_SUCCESS; > + } > +drop: > + kfree_skb(skb); > + return NET_RX_DROP; > +} > + > +static int pptp_rcv(struct sk_buff *skb) > +{ > + struct pppox_sock *po; > + struct pptp_gre_header *header; > + struct iphdr *iph; > + > + if (skb->pkt_type != PACKET_HOST) > + goto drop; > + > + if (!pskb_may_pull(skb, 12)) > + goto drop; > + > + iph = ip_hdr(skb); > + > + header = (struct pptp_gre_header *)skb->data; > + > + if ( /* version should be 1 */ > + ((header->ver & 0x7F) != PPTP_GRE_VER) || > + /* PPTP-GRE protocol for PPTP */ > + (ntohs(header->protocol) != PPTP_GRE_PROTO)|| > + /* flag C should be clear */ > + PPTP_GRE_IS_C(header->flags) || > + /* flag R should be clear */ > + PPTP_GRE_IS_R(header->flags) || > + /* flag K should be set */ > + (!PPTP_GRE_IS_K(header->flags)) || > + /* routing and recursion ctrl = 0 */ > + ((header->flags&0xF) != 0)) { > + /* if invalid, discard this packet */ > + goto drop; > + } > + > + > + if ((po=lookup_chan(htons(header->call_id),iph->saddr))) { > + skb_dst_drop(skb); > + skb_dst_set(skb,NULL); > + nf_reset(skb); > + return sk_receive_skb(sk_pppox(po), skb, 0); > + } > +drop: > + kfree_skb(skb); > + return NET_RX_DROP; > +} > + > +static int pptp_bind(struct socket *sock,struct sockaddr *uservaddr,int sockaddr_len) > +{ > + struct sock *sk = sock->sk; > + struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr; > + struct pppox_sock *po = pppox_sk(sk); > + struct pptp_opt *opt = &po->proto.pptp; > + int error = 0; > + > + lock_sock(sk); > + > + opt->src_addr = sp->sa_addr.pptp; > + if (add_chan(po)) { > + release_sock(sk); > + error = -EBUSY; > + } > + > + release_sock(sk); > + return error; > +} > + > +static int pptp_connect(struct socket *sock, struct sockaddr *uservaddr, > + int sockaddr_len, int flags) > +{ > + struct sock *sk = sock->sk; > + struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr; > + struct pppox_sock *po = pppox_sk(sk); > + struct pptp_opt *opt = &po->proto.pptp; > + struct rtable *rt; /* Route to the other host */ > + int error=0; > + > + if (sp->sa_protocol != PX_PROTO_PPTP) > + return -EINVAL; > + > + if (lookup_chan_dst(sp->sa_addr.pptp.call_id,sp->sa_addr.pptp.sin_addr.s_addr)) > + return -EALREADY; > + > + lock_sock(sk); > + /* Check for already bound sockets */ > + if (sk->sk_state & PPPOX_CONNECTED) { > + error = -EBUSY; > + goto end; > + } > + > + /* Check for already disconnected sockets, on attempts to disconnect */ > + if (sk->sk_state & PPPOX_DEAD) { > + error = -EALREADY; > + goto end; > + } > + > + if (!opt->src_addr.sin_addr.s_addr || !sp->sa_addr.pptp.sin_addr.s_addr) { > + error = -EINVAL; > + goto end; > + } > + > + po->chan.private = sk; > + po->chan.ops = &pptp_chan_ops; > + > + { > + struct flowi fl = { > + .nl_u = { .ip4_u = > + { .daddr = opt->dst_addr.sin_addr.s_addr, > + .saddr = opt->src_addr.sin_addr.s_addr, > + .tos = RT_CONN_FLAGS(sk) } }, > + .proto = IPPROTO_GRE }; > + security_sk_classify_flow(sk, &fl); > + if (ip_route_output_key(&init_net, &rt, &fl)) { > + error = -EHOSTUNREACH; > + goto end; > + } > + sk_setup_caps(sk, &rt->u.dst); > + } > + po->chan.mtu = dst_mtu(&rt->u.dst); > + if (!po->chan.mtu) po->chan.mtu = PPP_MTU; > + ip_rt_put(rt); > + po->chan.mtu -= PPTP_HEADER_OVERHEAD; > + > + po->chan.hdrlen = 2 + sizeof(struct pptp_gre_header); > + error = ppp_register_channel(&po->chan); > + if (error) { > + printk(KERN_ERR "PPTP: failed to register PPP channel (%d)\n",error); > + goto end; > + } > + > + opt->dst_addr = sp->sa_addr.pptp; > + sk->sk_state = PPPOX_CONNECTED; > + > + end: > + release_sock(sk); > + return error; > +} > + > +static int pptp_getname(struct socket *sock, struct sockaddr *uaddr, > + int *usockaddr_len, int peer) > +{ > + int len = sizeof(struct sockaddr_pppox); > + struct sockaddr_pppox sp; > + > + sp.sa_family = AF_PPPOX; > + sp.sa_protocol = PX_PROTO_PPTP; > + sp.sa_addr.pptp = pppox_sk(sock->sk)->proto.pptp.src_addr; > + > + memcpy(uaddr, &sp, len); > + > + *usockaddr_len = len; > + > + return 0; > +} > + > +static int pptp_release(struct socket *sock) > +{ > + struct sock *sk = sock->sk; > + struct pppox_sock *po; > + struct pptp_opt *opt; > + int error = 0; > + > + if (!sk) > + return 0; > + > + lock_sock(sk); > + > + if (sock_flag(sk, SOCK_DEAD)) { > + release_sock(sk); > + return -EBADF; > + } > + > + po = pppox_sk(sk); > + opt = &po->proto.pptp; > + del_chan(po); > + > + pppox_unbind_sock(sk); > + sk->sk_state = PPPOX_DEAD; > + > + sock_orphan(sk); > + sock->sk = NULL; > + > + release_sock(sk); > + sock_put(sk); > + > + return error; > +} > + > + > +static struct proto pptp_sk_proto = { static struct proto pptp_sk_proto __read_mostly = { > + .name = "PPTP", > + .owner = THIS_MODULE, > + .obj_size = sizeof(struct pppox_sock), > +}; > + > +static struct proto_ops pptp_ops = { static const > + .family = AF_PPPOX, > + .owner = THIS_MODULE, > + .release = pptp_release, > + .bind = pptp_bind, > + .connect = pptp_connect, > + .socketpair = sock_no_socketpair, > + .accept = sock_no_accept, > + .getname = pptp_getname, > + .poll = sock_no_poll, > + .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, > + .ioctl = pppox_ioctl, > +}; > + > +static void pptp_sock_destruct(struct sock *sk) > +{ > + if (!(sk->sk_state & PPPOX_DEAD)) { > + del_chan(pppox_sk(sk)); > + pppox_unbind_sock(sk); > + } > + skb_queue_purge(&sk->sk_receive_queue); > +} > +static int pptp_create(struct net *net, struct socket *sock) > +{ > + int error = -ENOMEM; > + struct sock *sk; > + struct pppox_sock *po; > + struct pptp_opt *opt; > + > + sk = sk_alloc(net,PF_PPPOX, GFP_KERNEL, &pptp_sk_proto); > + if (!sk) > + goto out; > + > + sock_init_data(sock, sk); > + > + sock->state = SS_UNCONNECTED; > + sock->ops = &pptp_ops; > + > + sk->sk_backlog_rcv = pptp_rcv_core; > + sk->sk_state = PPPOX_NONE; > + sk->sk_type = SOCK_STREAM; > + sk->sk_family = PF_PPPOX; > + sk->sk_protocol = PX_PROTO_PPTP; > + sk->sk_destruct = pptp_sock_destruct; > + > + po = pppox_sk(sk); > + opt = &po->proto.pptp; > + > + opt->seq_sent = 0; opt->seq_recv = 0; > + opt->ack_recv = 0; opt->ack_sent = 0; > + > + error = 0; > +out: > + return error; > +} > + > +static int pptp_ppp_ioctl(struct ppp_channel *chan, unsigned int cmd, > + unsigned long arg) > +{ > + struct sock *sk = (struct sock *) chan->private; > + struct pppox_sock *po = pppox_sk(sk); > + struct pptp_opt *opt = &po->proto.pptp; > + void __user *argp = (void __user *)arg; > + int __user *p = argp; > + int err, val; > + > + err = -EFAULT; > + switch (cmd) { > + case PPPIOCGFLAGS: > + val = opt->ppp_flags; > + if (put_user(val, p)) > + break; > + err = 0; > + break; > + case PPPIOCSFLAGS: > + if (get_user(val, p)) > + break; > + opt->ppp_flags = val & ~SC_RCV_BITS; > + err = 0; > + break; > + default: > + err = -ENOTTY; > + } > + > + return err; > +} > + > + > +static struct pppox_proto pppox_pptp_proto = { > + .create = pptp_create, > + .owner = THIS_MODULE, > +}; > + > + > +static struct gre_protocol gre_pptp_protocol = { > + .handler = pptp_rcv, > + //.err_handler = pptp_err, If you really want to use a comment, please use /* */ delimitors > +}; > + > +static int __init pptp_init_module(void) > +{ > + int err=0; > + printk(KERN_INFO "PPTP driver version " PPTP_DRIVER_VERSION "\n"); > + > + if (gre_add_protocol(&gre_pptp_protocol, GREPROTO_PPTP) < 0) { > + printk(KERN_INFO "PPTP: can't add protocol\n"); > + goto out; > + } > + > + err = proto_register(&pptp_sk_proto, 0); > + if (err) { > + printk(KERN_INFO "PPTP: can't register sk_proto\n"); > + goto out_inet_del_protocol; > + } > + > + err = register_pppox_proto(PX_PROTO_PPTP, &pppox_pptp_proto); > + if (err) { > + printk(KERN_INFO "PPTP: can't register pppox_proto\n"); > + goto out_unregister_sk_proto; > + } > + > + > + //assuming PAGESIZE is 4096 bytes Dont assume things like that ;) > + callid_bitmap = (unsigned long*)__get_free_pages(GFP_KERNEL,1); > + memset(callid_bitmap,0,PAGE_SIZE << 1); and prefer a kzalloc(65536/BITS_PER_BYTE, GFP_KERNEL) call here > + > +#if (BITS_PER_LONG == 32) > + callid_sock = (struct pppox_sock **)__get_free_pages(GFP_KERNEL,6); > + memset(callid_sock,0,PAGE_SIZE << 6); ditto here, please use vmalloc(65536 * sizeof(void *)) to avoid BITS_PER_LONG games > +#elif (BITS_PER_LONG == 64) > + callid_sock = (struct pppox_sock **)__get_free_pages(GFP_KERNEL,7); > + memset(callid_sock,0,PAGE_SIZE << 7); > +#else > +#error unknown size of LONG > +#endif > + > +out: > + return err; > +out_unregister_sk_proto: > + proto_unregister(&pptp_sk_proto); > +out_inet_del_protocol: > + gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP); > + return err; > +} > + > +static void __exit pptp_exit_module(void) > +{ > + unregister_pppox_proto(PX_PROTO_PPTP); > + proto_unregister(&pptp_sk_proto); > + gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP); > + if (callid_bitmap) free_pages((unsigned long)callid_bitmap,1); > + if (callid_sock) > +#if (BITS_PER_LONG == 32) > + free_pages((unsigned long)callid_sock,6); > +#elif (BITS_PER_LONG == 64) > + free_pages((unsigned long)callid_sock,7); > +#endif > +} > + > +module_init(pptp_init_module); > +module_exit(pptp_exit_module); > + > +MODULE_DESCRIPTION("Point-to-Point Tunneling Protocol"); > +MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); > +MODULE_LICENSE("GPL"); > + > diff --git a/include/linux/if_pppox.h b/include/linux/if_pppox.h > index a6577af..455ff56 100644 > --- a/include/linux/if_pppox.h > +++ b/include/linux/if_pppox.h > @@ -47,17 +47,27 @@ struct pppoe_addr{ > }; > > /************************************************************************ > + * PPTP addressing definition > + */ > +struct pptp_addr{ struct pptp_addr { > + __u16 call_id; > + struct in_addr sin_addr; > +}; > + > +/************************************************************************ > * Protocols supported by AF_PPPOX > */ > #define PX_PROTO_OE 0 /* Currently just PPPoE */ > #define PX_PROTO_OL2TP 1 /* Now L2TP also */ > -#define PX_MAX_PROTO 2 > +#define PX_PROTO_PPTP 2 > +#define PX_MAX_PROTO 3 > > struct sockaddr_pppox { > sa_family_t sa_family; /* address family, AF_PPPOX */ > unsigned int sa_protocol; /* protocol identifier */ > union{ > struct pppoe_addr pppoe; > + struct pptp_addr pptp; > }sa_addr; > }__attribute__ ((packed)); > > @@ -150,6 +160,13 @@ struct pppoe_opt { > relayed to (PPPoE relaying) */ > }; > > +struct pptp_opt { > + struct pptp_addr src_addr; > + struct pptp_addr dst_addr; > + __u32 ack_sent, ack_recv; > + __u32 seq_sent, seq_recv; > + int ppp_flags; > +}; > #include <net/sock.h> > > struct pppox_sock { > @@ -159,6 +176,7 @@ struct pppox_sock { > struct pppox_sock *next; /* for hash table */ > union { > struct pppoe_opt pppoe; > + struct pptp_opt pptp; > } proto; > __be16 num; > }; > diff --git a/include/net/gre.h b/include/net/gre.h > new file mode 100644 > index 0000000..31a0f76 > --- /dev/null > +++ b/include/net/gre.h > @@ -0,0 +1,18 @@ > +#ifndef __LINUX_GRE_H > +#define __LINUX_GRE_H > + > +#include <linux/skbuff.h> > + > +#define GREPROTO_CISCO 0 > +#define GREPROTO_PPTP 1 > +#define GREPROTO_MAX 2 > + > +struct gre_protocol { > + int (*handler)(struct sk_buff *skb); > + void (*err_handler)(struct sk_buff *skb, u32 info); > +}; > + > +int gre_add_protocol(const struct gre_protocol *proto, u8 version); > +int gre_del_protocol(const struct gre_protocol *proto, u8 version); > + > +#endif > diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig > index 7c3a7d1..7458bda 100644 > --- a/net/ipv4/Kconfig > +++ b/net/ipv4/Kconfig > @@ -215,8 +215,15 @@ config NET_IPIP > be inserted in and removed from the running kernel whenever you > want). Most people won't need this and can say N. > > +config NET_IPGRE_DEMUX > + tristate "IP: GRE demultiplexer" > + help > + This is helper module to demultiplex GRE packets on GRE version field criteria. > + Required by ip_gre and pptp modules. > + > config NET_IPGRE > tristate "IP: GRE tunnels over IP" > + depends on NET_IPGRE_DEMUX > help > Tunneling means encapsulating data of one protocol type within > another protocol and sending it over a channel that understands the > diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile > index 80ff87c..4978d22 100644 > --- a/net/ipv4/Makefile > +++ b/net/ipv4/Makefile > @@ -20,6 +20,7 @@ obj-$(CONFIG_PROC_FS) += proc.o > obj-$(CONFIG_IP_MULTIPLE_TABLES) += fib_rules.o > obj-$(CONFIG_IP_MROUTE) += ipmr.o > obj-$(CONFIG_NET_IPIP) += ipip.o > +obj-$(CONFIG_NET_IPGRE_DEMUX) += gre.o > obj-$(CONFIG_NET_IPGRE) += ip_gre.o > obj-$(CONFIG_SYN_COOKIES) += syncookies.o > obj-$(CONFIG_INET_AH) += ah4.o > diff --git a/net/ipv4/gre.c b/net/ipv4/gre.c > new file mode 100644 > index 0000000..f54a0fc > --- /dev/null > +++ b/net/ipv4/gre.c > @@ -0,0 +1,147 @@ > +/* > + * GRE over IPv4 demultiplexer driver > + * > + * Authors: Dmitry Kozlov (xeb@mail.ru) > + * > + * 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/module.h> > +#include <linux/kernel.h> > +#include <linux/kmod.h> > +#include <linux/skbuff.h> > +#include <linux/in.h> > +#include <linux/netdevice.h> > +#include <linux/version.h> > +#include <linux/spinlock.h> > +#include <net/protocol.h> > +#include <net/gre.h> > + > + > +const struct gre_protocol *gre_proto[GREPROTO_MAX] ____cacheline_aligned_in_smp; No need for ____cacheline_aligned_in_smp here. Better would be to user __read_mostly > +static DEFINE_RWLOCK(gre_proto_lock); This could use RCU and a spinlock instead > + > +int gre_add_protocol(const struct gre_protocol *proto, u8 version) > +{ > + int ret; > + > + if (version >= GREPROTO_MAX) > + return -1; > + > + write_lock_bh(&gre_proto_lock); > + if (gre_proto[version]) { > + ret = -1; > + } else { > + gre_proto[version]=proto; > + ret = 0; > + } > + write_unlock_bh(&gre_proto_lock); > + > + return ret; > +} > +int gre_del_protocol(const struct gre_protocol *proto, u8 version) > +{ > + int ret; > + > + if (version >= GREPROTO_MAX) > + return -1; > + > + write_lock_bh(&gre_proto_lock); > + if (gre_proto[version] == proto) { > + gre_proto[version] = NULL; > + ret = 0; > + } else { > + ret = -1; > + } > + write_unlock_bh(&gre_proto_lock); > + > + return ret; > +} > +static int gre_rcv(struct sk_buff *skb) > +{ > + u8 ver; > + int ret; > + > + if (!pskb_may_pull(skb, 12)) > + goto drop_nolock; > + > + ver = skb->data[1]&0x7f; > + if (ver >= GREPROTO_MAX) > + goto drop_nolock; > + > + read_lock(&gre_proto_lock); > + if (!gre_proto[ver] || !gre_proto[ver]->handler) > + goto drop; > + ret = gre_proto[ver]->handler(skb); > + read_unlock(&gre_proto_lock); rcu locking, no need to touch gre_proto_lock > + return ret; > + > +drop: > + read_unlock(&gre_proto_lock); > +drop_nolock: > + kfree_skb(skb); > + return NET_RX_DROP; > +} > +static void gre_err(struct sk_buff *skb, u32 info) > +{ > + u8 ver; > + > + printk("err\n"); not very usefull string > + > + if (!pskb_may_pull(skb, 12)) > + goto drop_nolock; > + > + ver=skb->data[1]; > + if (ver>=GREPROTO_MAX) > + goto drop_nolock; > + > + read_lock(&gre_proto_lock); > + if (!gre_proto[ver] || !gre_proto[ver]->err_handler) > + goto drop; > + gre_proto[ver]->err_handler(skb,info); > + read_unlock(&gre_proto_lock); > + return; > + > +drop: > + read_unlock(&gre_proto_lock); > +drop_nolock: > + kfree_skb(skb); > +} > + > + > +static struct net_protocol net_gre_protocol = { const ? > + .handler = gre_rcv, > + .err_handler = gre_err, > + .netns_ok=1, missing spaces around = > +}; > + > +static int __init gre_init(void) > +{ > + printk(KERN_INFO "GRE over IPv4 demultiplexor driver"); > + > + if (inet_add_protocol(&net_gre_protocol, IPPROTO_GRE) < 0) { > + printk(KERN_INFO "gre: can't add protocol\n"); > + return -EAGAIN; > + } > + > + return 0; > +} > + > +static void __exit gre_exit(void) > +{ > + inet_del_protocol(&net_gre_protocol, IPPROTO_GRE); > +} > + > +module_init(gre_init); > +module_exit(gre_exit); > + > +MODULE_DESCRIPTION("GRE over IPv4 demultiplexer driver"); > +MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); > +MODULE_LICENSE("GPL"); > +EXPORT_SYMBOL_GPL(gre_add_protocol); > +EXPORT_SYMBOL_GPL(gre_del_protocol); > + > diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c > index 32618e1..f0391b3 100644 > --- a/net/ipv4/ip_gre.c > +++ b/net/ipv4/ip_gre.c > @@ -44,6 +44,7 @@ > #include <net/net_namespace.h> > #include <net/netns/generic.h> > #include <net/rtnetlink.h> > +#include <net/gre.h> > > #ifdef CONFIG_IPV6 > #include <net/ipv6.h> > @@ -1276,10 +1277,9 @@ static void ipgre_fb_tunnel_init(struct net_device *dev) > } > > > -static const struct net_protocol ipgre_protocol = { > +static const struct gre_protocol ipgre_protocol = { > .handler = ipgre_rcv, > .err_handler = ipgre_err, > - .netns_ok = 1, > }; > > static void ipgre_destroy_tunnels(struct ipgre_net *ign, struct list_head *head) > @@ -1661,7 +1661,7 @@ static int __init ipgre_init(void) > if (err < 0) > return err; > > - err = inet_add_protocol(&ipgre_protocol, IPPROTO_GRE); > + err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); > if (err < 0) { > printk(KERN_INFO "ipgre init: can't add protocol\n"); > goto add_proto_failed; > @@ -1681,7 +1681,7 @@ out: > tap_ops_failed: > rtnl_link_unregister(&ipgre_link_ops); > rtnl_link_failed: > - inet_del_protocol(&ipgre_protocol, IPPROTO_GRE); > + gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); > add_proto_failed: > unregister_pernet_device(&ipgre_net_ops); > goto out; > @@ -1691,7 +1691,7 @@ static void __exit ipgre_fini(void) > { > rtnl_link_unregister(&ipgre_tap_ops); > rtnl_link_unregister(&ipgre_link_ops); > - if (inet_del_protocol(&ipgre_protocol, IPPROTO_GRE) < 0) > + if (gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO) < 0) > printk(KERN_INFO "ipgre close: can't remove protocol\n"); > unregister_pernet_device(&ipgre_net_ops); > } -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Eric! Thanks for comments. All your comments was accepted except: > > +static struct ppp_channel_ops pptp_chan_ops = { > > static const ? not, because po->chan.ops = &pptp_chan_ops which is not const > > +static DEFINE_RWLOCK(gre_proto_lock); > > This could use RCU and a spinlock instead > rcu + mutex Patch v4 will be ready soon... -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From: Dmitry Kozlov <xeb@mail.ru> Date: Wed, 18 Aug 2010 14:38:58 +0400 > Hi Eric! > Thanks for comments. All your comments was accepted except: > >> > +static struct ppp_channel_ops pptp_chan_ops = { >> >> static const ? > > not, because po->chan.ops = &pptp_chan_ops which is not const Yes it is: davem@sunset:~/src/GIT/linux-2.6$ git grep ppp_channel_ops -- include/linux/ include/linux/ppp_channel.h:struct ppp_channel_ops { include/linux/ppp_channel.h: const struct ppp_channel_ops *ops; /* operations for this channel */ davem@sunset:~/src/GIT/linux-2.6$ -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/MAINTAINERS b/MAINTAINERS index 02f75fc..191d7c4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6450,6 +6450,20 @@ M: "Maciej W. Rozycki" <macro@linux-mips.org> S: Maintained F: drivers/serial/zs.* +GRE DEMULTIPLEXER DRIVER +M: Dmitry Kozlov <D.Kozlov@protek-vrn.ru> +L: netdev@vger.kernel.org +S: Maintained +F: net/ipv4/gre.c +F: include/net/gre.h + +PPTP DRIVER +M: Dmitry Kozlov <D.Kozlov@protek-vrn.ru> +L: netdev@vger.kernel.org +S: Maintained +F: drivers/net/pptp.c +W: http://sourceforge.net/projects/accel-pptp + THE REST M: Linus Torvalds <torvalds@linux-foundation.org> L: linux-kernel@vger.kernel.org diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index ce2fcdd..2fa0516 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -3167,6 +3167,17 @@ config PPPOE which contains instruction on how to use this driver (under the heading "Kernel mode PPPoE"). +config PPTP + tristate "PPP over IPv4 (PPTP) (EXPERIMENTAL)" + depends on EXPERIMENTAL && PPP && NET_IPGRE_DEMUX + help + Support for PPP over IPv4.(Point-to-Point Tunneling Protocol) + + This driver requires pppd plugin to work in client mode or + modified pptpd (poptop) to work in server mode. + See http://accel-pptp.sourceforge.net/ for information how to + utilize this module. + config PPPOATM tristate "PPP over ATM" depends on ATM && PPP diff --git a/drivers/net/Makefile b/drivers/net/Makefile index 0a0512a..b33fef1 100644 --- a/drivers/net/Makefile +++ b/drivers/net/Makefile @@ -162,6 +162,7 @@ obj-$(CONFIG_PPP_BSDCOMP) += bsd_comp.o obj-$(CONFIG_PPP_MPPE) += ppp_mppe.o obj-$(CONFIG_PPPOE) += pppox.o pppoe.o obj-$(CONFIG_PPPOL2TP) += pppox.o +obj-$(CONFIG_PPTP) += pppox.o pptp.o obj-$(CONFIG_SLIP) += slip.o obj-$(CONFIG_SLHC) += slhc.o diff --git a/drivers/net/pptp.c b/drivers/net/pptp.c new file mode 100644 index 0000000..5dad2f0 --- /dev/null +++ b/drivers/net/pptp.c @@ -0,0 +1,747 @@ +/* + * Point-to-Point Tunneling Protocol for Linux + * + * Authors: Dmitry Kozlov <xeb@mail.ru> + * + * 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/string.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/errno.h> +#include <linux/netdevice.h> +#include <linux/net.h> +#include <linux/skbuff.h> +#include <linux/init.h> +#include <linux/ppp_channel.h> +#include <linux/ppp_defs.h> +#include <linux/if_pppox.h> +#include <linux/if_ppp.h> +#include <linux/notifier.h> +#include <linux/file.h> +#include <linux/in.h> +#include <linux/ip.h> +#include <linux/netfilter.h> +#include <linux/netfilter_ipv4.h> +#include <linux/version.h> +//#include <linux/spinlock.h> +#include <linux/rcupdate.h> +#include <linux/semaphore.h> + + +#include <net/sock.h> +#include <net/protocol.h> +#include <net/ip.h> +#include <net/icmp.h> +#include <net/route.h> +#include <net/gre.h> + +#include <asm/uaccess.h> + +#define PPTP_DRIVER_VERSION "0.8.4" + +#define MAX_CALLID 65535 +#define PPP_LCP_ECHOREQ 0x09 +#define PPP_LCP_ECHOREP 0x0A +#define SC_RCV_BITS (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP) + +static unsigned long *callid_bitmap = NULL; +static struct pppox_sock **callid_sock=NULL; + + +static DECLARE_MUTEX(chan_lock); + +static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb); +static int pptp_ppp_ioctl(struct ppp_channel *chan, unsigned int cmd, + unsigned long arg); +static int pptp_rcv_core(struct sock *sk,struct sk_buff *skb); + +static struct ppp_channel_ops pptp_chan_ops = { + .start_xmit = pptp_xmit, + .ioctl = pptp_ppp_ioctl, +}; + + +#define MISSING_WINDOW 20 +#define WRAPPED( curseq, lastseq) \ + ((((curseq) & 0xffffff00) == 0) && \ + (((lastseq) & 0xffffff00 ) == 0xffffff00)) + +/* gre header structure: -------------------------------------------- */ + +#define PPTP_GRE_PROTO 0x880B +#define PPTP_GRE_VER 0x1 + +#define PPTP_GRE_FLAG_C 0x80 +#define PPTP_GRE_FLAG_R 0x40 +#define PPTP_GRE_FLAG_K 0x20 +#define PPTP_GRE_FLAG_S 0x10 +#define PPTP_GRE_FLAG_A 0x80 + +#define PPTP_GRE_IS_C(f) ((f)&PPTP_GRE_FLAG_C) +#define PPTP_GRE_IS_R(f) ((f)&PPTP_GRE_FLAG_R) +#define PPTP_GRE_IS_K(f) ((f)&PPTP_GRE_FLAG_K) +#define PPTP_GRE_IS_S(f) ((f)&PPTP_GRE_FLAG_S) +#define PPTP_GRE_IS_A(f) ((f)&PPTP_GRE_FLAG_A) + +#define PPTP_HEADER_OVERHEAD (2+sizeof(struct pptp_gre_header)) +struct pptp_gre_header { + u8 flags; /* bitfield */ + u8 ver; /* should be PPTP_GRE_VER (enhanced GRE) */ + u16 protocol; /* should be PPTP_GRE_PROTO (ppp-encaps) */ + u16 payload_len; /* size of ppp payload, not inc. gre header */ + u16 call_id; /* peer's call_id for this session */ + u32 seq; /* sequence number. Present if S==1 */ + u32 ack; /* seq number of highest packet recieved by */ + /* sender in this session */ +}; + +static struct pppox_sock * lookup_chan(__u16 call_id, __be32 s_addr) +{ + struct pppox_sock *sock; + struct pptp_opt *opt; + + rcu_read_lock(); + sock = rcu_dereference(callid_sock[call_id]); + if (sock) { + opt = &sock->proto.pptp; + if (opt->dst_addr.sin_addr.s_addr != s_addr) sock = NULL; + else sock_hold(sk_pppox(sock)); + } + rcu_read_unlock(); + + return sock; +} + +static int lookup_chan_dst(__u16 call_id, __be32 d_addr) +{ + struct pppox_sock *sock; + struct pptp_opt *opt; + int i; + + down(&chan_lock); + for(i = find_next_bit(callid_bitmap,MAX_CALLID,1); i < MAX_CALLID; i = find_next_bit(callid_bitmap,MAX_CALLID,i+1)) { + sock = callid_sock[i]; + opt = &sock->proto.pptp; + if (opt->dst_addr.call_id == call_id && opt->dst_addr.sin_addr.s_addr == d_addr) break; + } + up(&chan_lock); + + return i < MAX_CALLID; +} + +static int add_chan(struct pppox_sock *sock) +{ + static int call_id = 0; + int res = -1; + + synchronize_rcu(); + + down(&chan_lock); + if (!sock->proto.pptp.src_addr.call_id) { + call_id = find_next_zero_bit(callid_bitmap,MAX_CALLID,call_id+1); + if (call_id == MAX_CALLID) + call_id = find_next_zero_bit(callid_bitmap,MAX_CALLID,1); + sock->proto.pptp.src_addr.call_id = call_id; + } else if (test_bit(sock->proto.pptp.src_addr.call_id,callid_bitmap)) + goto exit; + + set_bit(sock->proto.pptp.src_addr.call_id,callid_bitmap); + rcu_assign_pointer(callid_sock[sock->proto.pptp.src_addr.call_id],sock); + res = 0; + +exit: + up(&chan_lock); + + return res; +} + +static void del_chan(struct pppox_sock *sock) +{ + synchronize_rcu(); + + down(&chan_lock); + clear_bit(sock->proto.pptp.src_addr.call_id,callid_bitmap); + rcu_assign_pointer(callid_sock[sock->proto.pptp.src_addr.call_id],NULL); + up(&chan_lock); +} + +static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb) +{ + struct sock *sk = (struct sock *) chan->private; + struct pppox_sock *po = pppox_sk(sk); + struct pptp_opt *opt = &po->proto.pptp; + struct pptp_gre_header *hdr; + unsigned int header_len = sizeof(*hdr); + int err = 0; + int islcp; + int len; + unsigned char *data; + __u32 seq_recv; + + + struct rtable *rt; /* Route to the other host */ + struct net_device *tdev; /* Device to other host */ + struct iphdr *iph; /* Our new IP header */ + int max_headroom; /* The extra header space needed */ + + if (sk_pppox(po)->sk_state & PPPOX_DEAD) + goto tx_error; + + { + struct flowi fl = { .oif = 0, + .nl_u = { .ip4_u = + { .daddr = opt->dst_addr.sin_addr.s_addr, + .saddr = opt->src_addr.sin_addr.s_addr, + .tos = RT_TOS(0) } }, + .proto = IPPROTO_GRE }; + if ((err=ip_route_output_key(&init_net,&rt, &fl))) { + goto tx_error; + } + } + tdev = rt->u.dst.dev; + + max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(*iph)+sizeof(*hdr)+2; + + if (skb_headroom(skb) < max_headroom || skb_cloned(skb) || skb_shared(skb)) { + struct sk_buff *new_skb = skb_realloc_headroom(skb, max_headroom); + if (!new_skb) { + ip_rt_put(rt); + goto tx_error; + } + if (skb->sk) + skb_set_owner_w(new_skb, skb->sk); + kfree_skb(skb); + skb = new_skb; + } + + data = skb->data; + islcp = ((data[0] << 8) + data[1])== PPP_LCP && 1 <= data[2] && data[2] <= 7; + + /* compress protocol field */ + if ((opt->ppp_flags & SC_COMP_PROT) && data[0] == 0 && !islcp) + skb_pull(skb,1); + + /* + * Put in the address/control bytes if necessary + */ + if ((opt->ppp_flags & SC_COMP_AC) == 0 || islcp) { + data = skb_push(skb,2); + data[0] = PPP_ALLSTATIONS; + data[1] = PPP_UI; + } + + len = skb->len; + + seq_recv = opt->seq_recv; + + if (opt->ack_sent == seq_recv) header_len -= sizeof(hdr->ack); + + // Push down and install GRE header + skb_push(skb,header_len); + hdr = (struct pptp_gre_header *)(skb->data); + + hdr->flags = PPTP_GRE_FLAG_K; + hdr->ver = PPTP_GRE_VER; + hdr->protocol = htons(PPTP_GRE_PROTO); + hdr->call_id = htons(opt->dst_addr.call_id); + + hdr->flags |= PPTP_GRE_FLAG_S; + hdr->seq = htonl(++opt->seq_sent); + if (opt->ack_sent != seq_recv) { + /* send ack with this message */ + hdr->ver |= PPTP_GRE_FLAG_A; + hdr->ack = htonl(seq_recv); + opt->ack_sent = seq_recv; + } + hdr->payload_len = htons(len); + + /* + * Push down and install the IP header. + */ + + skb_reset_transport_header(skb); + skb_push(skb, sizeof(*iph)); + skb_reset_network_header(skb); + memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt)); + IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED | IPSKB_REROUTED); + + iph = ip_hdr(skb); + iph->version = 4; + iph->ihl = sizeof(struct iphdr) >> 2; + if (ip_dont_fragment(sk, &rt->u.dst)) + iph->frag_off = htons(IP_DF); + else + iph->frag_off = 0; + iph->protocol = IPPROTO_GRE; + iph->tos = 0; + iph->daddr = rt->rt_dst; + iph->saddr = rt->rt_src; + iph->ttl = dst_metric(&rt->u.dst, RTAX_HOPLIMIT); + iph->tot_len = htons(skb->len); + + skb_dst_drop(skb); + skb_dst_set(skb,&rt->u.dst); + + nf_reset(skb); + + skb->ip_summed = CHECKSUM_NONE; + ip_select_ident(iph, &rt->u.dst, NULL); + ip_send_check(iph); + + ip_local_out(skb); + +tx_error: + return 1; +} + +static int pptp_rcv_core(struct sock *sk,struct sk_buff *skb) +{ + struct pppox_sock *po = pppox_sk(sk); + struct pptp_opt *opt = &po->proto.pptp; + int headersize,payload_len,seq; + __u8 *payload; + struct pptp_gre_header *header; + + if (!(sk->sk_state & PPPOX_CONNECTED)) { + if (sock_queue_rcv_skb(sk, skb)) + goto drop; + return NET_RX_SUCCESS; + } + + header = (struct pptp_gre_header *)(skb->data); + + /* test if acknowledgement present */ + if (PPTP_GRE_IS_A(header->ver)) { + __u32 ack = (PPTP_GRE_IS_S(header->flags))? + header->ack:header->seq; /* ack in different place if S = 0 */ + + ack = ntohl( ack); + + if (ack > opt->ack_recv) opt->ack_recv = ack; + /* also handle sequence number wrap-around */ + if (WRAPPED(ack,opt->ack_recv)) opt->ack_recv = ack; + } + + /* test if payload present */ + if (!PPTP_GRE_IS_S(header->flags)) { + goto drop; + } + + headersize = sizeof(*header); + payload_len = ntohs(header->payload_len); + seq = ntohl(header->seq); + + /* no ack present? */ + if (!PPTP_GRE_IS_A(header->ver)) headersize -= sizeof(header->ack); + /* check for incomplete packet (length smaller than expected) */ + if (skb->len - headersize < payload_len) { + goto drop; + } + + payload = skb->data+headersize; + /* check for expected sequence number */ + if ( seq < opt->seq_recv + 1 || WRAPPED(opt->seq_recv, seq) ) { + if ( (payload[0] == PPP_ALLSTATIONS) && (payload[1] == PPP_UI) && + (PPP_PROTOCOL(payload) == PPP_LCP) && + ((payload[4] == PPP_LCP_ECHOREQ) || (payload[4] == PPP_LCP_ECHOREP)) ) { + goto allow_packet; + } + }else{ + opt->seq_recv = seq; +allow_packet: + skb_pull(skb,headersize); + + if (payload[0] == PPP_ALLSTATIONS && payload[1] == PPP_UI) { + /* chop off address/control */ + if (skb->len < 3) + goto drop; + skb_pull(skb,2); + } + + if ((*skb->data) & 1) { + /* protocol is compressed */ + skb_push(skb, 1)[0] = 0; + } + + skb->ip_summed = CHECKSUM_NONE; + skb_set_network_header(skb,skb->head-skb->data); + ppp_input(&po->chan,skb); + + return NET_RX_SUCCESS; + } +drop: + kfree_skb(skb); + return NET_RX_DROP; +} + +static int pptp_rcv(struct sk_buff *skb) +{ + struct pppox_sock *po; + struct pptp_gre_header *header; + struct iphdr *iph; + + if (skb->pkt_type != PACKET_HOST) + goto drop; + + if (!pskb_may_pull(skb, 12)) + goto drop; + + iph = ip_hdr(skb); + + header = (struct pptp_gre_header *)skb->data; + + if ( /* version should be 1 */ + ((header->ver & 0x7F) != PPTP_GRE_VER) || + /* PPTP-GRE protocol for PPTP */ + (ntohs(header->protocol) != PPTP_GRE_PROTO)|| + /* flag C should be clear */ + PPTP_GRE_IS_C(header->flags) || + /* flag R should be clear */ + PPTP_GRE_IS_R(header->flags) || + /* flag K should be set */ + (!PPTP_GRE_IS_K(header->flags)) || + /* routing and recursion ctrl = 0 */ + ((header->flags&0xF) != 0)) { + /* if invalid, discard this packet */ + goto drop; + } + + + if ((po=lookup_chan(htons(header->call_id),iph->saddr))) { + skb_dst_drop(skb); + skb_dst_set(skb,NULL); + nf_reset(skb); + return sk_receive_skb(sk_pppox(po), skb, 0); + } +drop: + kfree_skb(skb); + return NET_RX_DROP; +} + +static int pptp_bind(struct socket *sock,struct sockaddr *uservaddr,int sockaddr_len) +{ + struct sock *sk = sock->sk; + struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr; + struct pppox_sock *po = pppox_sk(sk); + struct pptp_opt *opt = &po->proto.pptp; + int error = 0; + + lock_sock(sk); + + opt->src_addr = sp->sa_addr.pptp; + if (add_chan(po)) { + release_sock(sk); + error = -EBUSY; + } + + release_sock(sk); + return error; +} + +static int pptp_connect(struct socket *sock, struct sockaddr *uservaddr, + int sockaddr_len, int flags) +{ + struct sock *sk = sock->sk; + struct sockaddr_pppox *sp = (struct sockaddr_pppox *) uservaddr; + struct pppox_sock *po = pppox_sk(sk); + struct pptp_opt *opt = &po->proto.pptp; + struct rtable *rt; /* Route to the other host */ + int error=0; + + if (sp->sa_protocol != PX_PROTO_PPTP) + return -EINVAL; + + if (lookup_chan_dst(sp->sa_addr.pptp.call_id,sp->sa_addr.pptp.sin_addr.s_addr)) + return -EALREADY; + + lock_sock(sk); + /* Check for already bound sockets */ + if (sk->sk_state & PPPOX_CONNECTED) { + error = -EBUSY; + goto end; + } + + /* Check for already disconnected sockets, on attempts to disconnect */ + if (sk->sk_state & PPPOX_DEAD) { + error = -EALREADY; + goto end; + } + + if (!opt->src_addr.sin_addr.s_addr || !sp->sa_addr.pptp.sin_addr.s_addr) { + error = -EINVAL; + goto end; + } + + po->chan.private = sk; + po->chan.ops = &pptp_chan_ops; + + { + struct flowi fl = { + .nl_u = { .ip4_u = + { .daddr = opt->dst_addr.sin_addr.s_addr, + .saddr = opt->src_addr.sin_addr.s_addr, + .tos = RT_CONN_FLAGS(sk) } }, + .proto = IPPROTO_GRE }; + security_sk_classify_flow(sk, &fl); + if (ip_route_output_key(&init_net, &rt, &fl)) { + error = -EHOSTUNREACH; + goto end; + } + sk_setup_caps(sk, &rt->u.dst); + } + po->chan.mtu = dst_mtu(&rt->u.dst); + if (!po->chan.mtu) po->chan.mtu = PPP_MTU; + ip_rt_put(rt); + po->chan.mtu -= PPTP_HEADER_OVERHEAD; + + po->chan.hdrlen = 2 + sizeof(struct pptp_gre_header); + error = ppp_register_channel(&po->chan); + if (error) { + printk(KERN_ERR "PPTP: failed to register PPP channel (%d)\n",error); + goto end; + } + + opt->dst_addr = sp->sa_addr.pptp; + sk->sk_state = PPPOX_CONNECTED; + + end: + release_sock(sk); + return error; +} + +static int pptp_getname(struct socket *sock, struct sockaddr *uaddr, + int *usockaddr_len, int peer) +{ + int len = sizeof(struct sockaddr_pppox); + struct sockaddr_pppox sp; + + sp.sa_family = AF_PPPOX; + sp.sa_protocol = PX_PROTO_PPTP; + sp.sa_addr.pptp = pppox_sk(sock->sk)->proto.pptp.src_addr; + + memcpy(uaddr, &sp, len); + + *usockaddr_len = len; + + return 0; +} + +static int pptp_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct pppox_sock *po; + struct pptp_opt *opt; + int error = 0; + + if (!sk) + return 0; + + lock_sock(sk); + + if (sock_flag(sk, SOCK_DEAD)) { + release_sock(sk); + return -EBADF; + } + + po = pppox_sk(sk); + opt = &po->proto.pptp; + del_chan(po); + + pppox_unbind_sock(sk); + sk->sk_state = PPPOX_DEAD; + + sock_orphan(sk); + sock->sk = NULL; + + release_sock(sk); + sock_put(sk); + + return error; +} + + +static struct proto pptp_sk_proto = { + .name = "PPTP", + .owner = THIS_MODULE, + .obj_size = sizeof(struct pppox_sock), +}; + +static struct proto_ops pptp_ops = { + .family = AF_PPPOX, + .owner = THIS_MODULE, + .release = pptp_release, + .bind = pptp_bind, + .connect = pptp_connect, + .socketpair = sock_no_socketpair, + .accept = sock_no_accept, + .getname = pptp_getname, + .poll = sock_no_poll, + .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, + .ioctl = pppox_ioctl, +}; + +static void pptp_sock_destruct(struct sock *sk) +{ + if (!(sk->sk_state & PPPOX_DEAD)) { + del_chan(pppox_sk(sk)); + pppox_unbind_sock(sk); + } + skb_queue_purge(&sk->sk_receive_queue); +} +static int pptp_create(struct net *net, struct socket *sock) +{ + int error = -ENOMEM; + struct sock *sk; + struct pppox_sock *po; + struct pptp_opt *opt; + + sk = sk_alloc(net,PF_PPPOX, GFP_KERNEL, &pptp_sk_proto); + if (!sk) + goto out; + + sock_init_data(sock, sk); + + sock->state = SS_UNCONNECTED; + sock->ops = &pptp_ops; + + sk->sk_backlog_rcv = pptp_rcv_core; + sk->sk_state = PPPOX_NONE; + sk->sk_type = SOCK_STREAM; + sk->sk_family = PF_PPPOX; + sk->sk_protocol = PX_PROTO_PPTP; + sk->sk_destruct = pptp_sock_destruct; + + po = pppox_sk(sk); + opt = &po->proto.pptp; + + opt->seq_sent = 0; opt->seq_recv = 0; + opt->ack_recv = 0; opt->ack_sent = 0; + + error = 0; +out: + return error; +} + +static int pptp_ppp_ioctl(struct ppp_channel *chan, unsigned int cmd, + unsigned long arg) +{ + struct sock *sk = (struct sock *) chan->private; + struct pppox_sock *po = pppox_sk(sk); + struct pptp_opt *opt = &po->proto.pptp; + void __user *argp = (void __user *)arg; + int __user *p = argp; + int err, val; + + err = -EFAULT; + switch (cmd) { + case PPPIOCGFLAGS: + val = opt->ppp_flags; + if (put_user(val, p)) + break; + err = 0; + break; + case PPPIOCSFLAGS: + if (get_user(val, p)) + break; + opt->ppp_flags = val & ~SC_RCV_BITS; + err = 0; + break; + default: + err = -ENOTTY; + } + + return err; +} + + +static struct pppox_proto pppox_pptp_proto = { + .create = pptp_create, + .owner = THIS_MODULE, +}; + + +static struct gre_protocol gre_pptp_protocol = { + .handler = pptp_rcv, + //.err_handler = pptp_err, +}; + +static int __init pptp_init_module(void) +{ + int err=0; + printk(KERN_INFO "PPTP driver version " PPTP_DRIVER_VERSION "\n"); + + if (gre_add_protocol(&gre_pptp_protocol, GREPROTO_PPTP) < 0) { + printk(KERN_INFO "PPTP: can't add protocol\n"); + goto out; + } + + err = proto_register(&pptp_sk_proto, 0); + if (err) { + printk(KERN_INFO "PPTP: can't register sk_proto\n"); + goto out_inet_del_protocol; + } + + err = register_pppox_proto(PX_PROTO_PPTP, &pppox_pptp_proto); + if (err) { + printk(KERN_INFO "PPTP: can't register pppox_proto\n"); + goto out_unregister_sk_proto; + } + + + //assuming PAGESIZE is 4096 bytes + callid_bitmap = (unsigned long*)__get_free_pages(GFP_KERNEL,1); + memset(callid_bitmap,0,PAGE_SIZE << 1); + +#if (BITS_PER_LONG == 32) + callid_sock = (struct pppox_sock **)__get_free_pages(GFP_KERNEL,6); + memset(callid_sock,0,PAGE_SIZE << 6); +#elif (BITS_PER_LONG == 64) + callid_sock = (struct pppox_sock **)__get_free_pages(GFP_KERNEL,7); + memset(callid_sock,0,PAGE_SIZE << 7); +#else +#error unknown size of LONG +#endif + +out: + return err; +out_unregister_sk_proto: + proto_unregister(&pptp_sk_proto); +out_inet_del_protocol: + gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP); + return err; +} + +static void __exit pptp_exit_module(void) +{ + unregister_pppox_proto(PX_PROTO_PPTP); + proto_unregister(&pptp_sk_proto); + gre_del_protocol(&gre_pptp_protocol, GREPROTO_PPTP); + if (callid_bitmap) free_pages((unsigned long)callid_bitmap,1); + if (callid_sock) +#if (BITS_PER_LONG == 32) + free_pages((unsigned long)callid_sock,6); +#elif (BITS_PER_LONG == 64) + free_pages((unsigned long)callid_sock,7); +#endif +} + +module_init(pptp_init_module); +module_exit(pptp_exit_module); + +MODULE_DESCRIPTION("Point-to-Point Tunneling Protocol"); +MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); +MODULE_LICENSE("GPL"); + diff --git a/include/linux/if_pppox.h b/include/linux/if_pppox.h index a6577af..455ff56 100644 --- a/include/linux/if_pppox.h +++ b/include/linux/if_pppox.h @@ -47,17 +47,27 @@ struct pppoe_addr{ }; /************************************************************************ + * PPTP addressing definition + */ +struct pptp_addr{ + __u16 call_id; + struct in_addr sin_addr; +}; + +/************************************************************************ * Protocols supported by AF_PPPOX */ #define PX_PROTO_OE 0 /* Currently just PPPoE */ #define PX_PROTO_OL2TP 1 /* Now L2TP also */ -#define PX_MAX_PROTO 2 +#define PX_PROTO_PPTP 2 +#define PX_MAX_PROTO 3 struct sockaddr_pppox { sa_family_t sa_family; /* address family, AF_PPPOX */ unsigned int sa_protocol; /* protocol identifier */ union{ struct pppoe_addr pppoe; + struct pptp_addr pptp; }sa_addr; }__attribute__ ((packed)); @@ -150,6 +160,13 @@ struct pppoe_opt { relayed to (PPPoE relaying) */ }; +struct pptp_opt { + struct pptp_addr src_addr; + struct pptp_addr dst_addr; + __u32 ack_sent, ack_recv; + __u32 seq_sent, seq_recv; + int ppp_flags; +}; #include <net/sock.h> struct pppox_sock { @@ -159,6 +176,7 @@ struct pppox_sock { struct pppox_sock *next; /* for hash table */ union { struct pppoe_opt pppoe; + struct pptp_opt pptp; } proto; __be16 num; }; diff --git a/include/net/gre.h b/include/net/gre.h new file mode 100644 index 0000000..31a0f76 --- /dev/null +++ b/include/net/gre.h @@ -0,0 +1,18 @@ +#ifndef __LINUX_GRE_H +#define __LINUX_GRE_H + +#include <linux/skbuff.h> + +#define GREPROTO_CISCO 0 +#define GREPROTO_PPTP 1 +#define GREPROTO_MAX 2 + +struct gre_protocol { + int (*handler)(struct sk_buff *skb); + void (*err_handler)(struct sk_buff *skb, u32 info); +}; + +int gre_add_protocol(const struct gre_protocol *proto, u8 version); +int gre_del_protocol(const struct gre_protocol *proto, u8 version); + +#endif diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig index 7c3a7d1..7458bda 100644 --- a/net/ipv4/Kconfig +++ b/net/ipv4/Kconfig @@ -215,8 +215,15 @@ config NET_IPIP be inserted in and removed from the running kernel whenever you want). Most people won't need this and can say N. +config NET_IPGRE_DEMUX + tristate "IP: GRE demultiplexer" + help + This is helper module to demultiplex GRE packets on GRE version field criteria. + Required by ip_gre and pptp modules. + config NET_IPGRE tristate "IP: GRE tunnels over IP" + depends on NET_IPGRE_DEMUX help Tunneling means encapsulating data of one protocol type within another protocol and sending it over a channel that understands the diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile index 80ff87c..4978d22 100644 --- a/net/ipv4/Makefile +++ b/net/ipv4/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_PROC_FS) += proc.o obj-$(CONFIG_IP_MULTIPLE_TABLES) += fib_rules.o obj-$(CONFIG_IP_MROUTE) += ipmr.o obj-$(CONFIG_NET_IPIP) += ipip.o +obj-$(CONFIG_NET_IPGRE_DEMUX) += gre.o obj-$(CONFIG_NET_IPGRE) += ip_gre.o obj-$(CONFIG_SYN_COOKIES) += syncookies.o obj-$(CONFIG_INET_AH) += ah4.o diff --git a/net/ipv4/gre.c b/net/ipv4/gre.c new file mode 100644 index 0000000..f54a0fc --- /dev/null +++ b/net/ipv4/gre.c @@ -0,0 +1,147 @@ +/* + * GRE over IPv4 demultiplexer driver + * + * Authors: Dmitry Kozlov (xeb@mail.ru) + * + * 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/module.h> +#include <linux/kernel.h> +#include <linux/kmod.h> +#include <linux/skbuff.h> +#include <linux/in.h> +#include <linux/netdevice.h> +#include <linux/version.h> +#include <linux/spinlock.h> +#include <net/protocol.h> +#include <net/gre.h> + + +const struct gre_protocol *gre_proto[GREPROTO_MAX] ____cacheline_aligned_in_smp; +static DEFINE_RWLOCK(gre_proto_lock); + +int gre_add_protocol(const struct gre_protocol *proto, u8 version) +{ + int ret; + + if (version >= GREPROTO_MAX) + return -1; + + write_lock_bh(&gre_proto_lock); + if (gre_proto[version]) { + ret = -1; + } else { + gre_proto[version]=proto; + ret = 0; + } + write_unlock_bh(&gre_proto_lock); + + return ret; +} +int gre_del_protocol(const struct gre_protocol *proto, u8 version) +{ + int ret; + + if (version >= GREPROTO_MAX) + return -1; + + write_lock_bh(&gre_proto_lock); + if (gre_proto[version] == proto) { + gre_proto[version] = NULL; + ret = 0; + } else { + ret = -1; + } + write_unlock_bh(&gre_proto_lock); + + return ret; +} +static int gre_rcv(struct sk_buff *skb) +{ + u8 ver; + int ret; + + if (!pskb_may_pull(skb, 12)) + goto drop_nolock; + + ver = skb->data[1]&0x7f; + if (ver >= GREPROTO_MAX) + goto drop_nolock; + + read_lock(&gre_proto_lock); + if (!gre_proto[ver] || !gre_proto[ver]->handler) + goto drop; + ret = gre_proto[ver]->handler(skb); + read_unlock(&gre_proto_lock); + return ret; + +drop: + read_unlock(&gre_proto_lock); +drop_nolock: + kfree_skb(skb); + return NET_RX_DROP; +} +static void gre_err(struct sk_buff *skb, u32 info) +{ + u8 ver; + + printk("err\n"); + + if (!pskb_may_pull(skb, 12)) + goto drop_nolock; + + ver=skb->data[1]; + if (ver>=GREPROTO_MAX) + goto drop_nolock; + + read_lock(&gre_proto_lock); + if (!gre_proto[ver] || !gre_proto[ver]->err_handler) + goto drop; + gre_proto[ver]->err_handler(skb,info); + read_unlock(&gre_proto_lock); + return; + +drop: + read_unlock(&gre_proto_lock); +drop_nolock: + kfree_skb(skb); +} + + +static struct net_protocol net_gre_protocol = { + .handler = gre_rcv, + .err_handler = gre_err, + .netns_ok=1, +}; + +static int __init gre_init(void) +{ + printk(KERN_INFO "GRE over IPv4 demultiplexor driver"); + + if (inet_add_protocol(&net_gre_protocol, IPPROTO_GRE) < 0) { + printk(KERN_INFO "gre: can't add protocol\n"); + return -EAGAIN; + } + + return 0; +} + +static void __exit gre_exit(void) +{ + inet_del_protocol(&net_gre_protocol, IPPROTO_GRE); +} + +module_init(gre_init); +module_exit(gre_exit); + +MODULE_DESCRIPTION("GRE over IPv4 demultiplexer driver"); +MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); +MODULE_LICENSE("GPL"); +EXPORT_SYMBOL_GPL(gre_add_protocol); +EXPORT_SYMBOL_GPL(gre_del_protocol); + diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 32618e1..f0391b3 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -44,6 +44,7 @@ #include <net/net_namespace.h> #include <net/netns/generic.h> #include <net/rtnetlink.h> +#include <net/gre.h> #ifdef CONFIG_IPV6 #include <net/ipv6.h> @@ -1276,10 +1277,9 @@ static void ipgre_fb_tunnel_init(struct net_device *dev) } -static const struct net_protocol ipgre_protocol = { +static const struct gre_protocol ipgre_protocol = { .handler = ipgre_rcv, .err_handler = ipgre_err, - .netns_ok = 1, }; static void ipgre_destroy_tunnels(struct ipgre_net *ign, struct list_head *head) @@ -1661,7 +1661,7 @@ static int __init ipgre_init(void) if (err < 0) return err; - err = inet_add_protocol(&ipgre_protocol, IPPROTO_GRE); + err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); if (err < 0) { printk(KERN_INFO "ipgre init: can't add protocol\n"); goto add_proto_failed; @@ -1681,7 +1681,7 @@ out: tap_ops_failed: rtnl_link_unregister(&ipgre_link_ops); rtnl_link_failed: - inet_del_protocol(&ipgre_protocol, IPPROTO_GRE); + gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); add_proto_failed: unregister_pernet_device(&ipgre_net_ops); goto out; @@ -1691,7 +1691,7 @@ static void __exit ipgre_fini(void) { rtnl_link_unregister(&ipgre_tap_ops); rtnl_link_unregister(&ipgre_link_ops); - if (inet_del_protocol(&ipgre_protocol, IPPROTO_GRE) < 0) + if (gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO) < 0) printk(KERN_INFO "ipgre close: can't remove protocol\n"); unregister_pernet_device(&ipgre_net_ops); }