[L2TP]: Changes to existing ppp and socket kernel headers for L2TP

Add struct sockaddr_pppol2tp to carry L2TP-specific address
information for the PPPoX (PPPoL2TP) socket. Unfortunately we can't
use the union inside struct sockaddr_pppox because the L2TP-specific
data is larger than the current size of the union and we must preserve
the size of struct sockaddr_pppox for binary compatibility.

Also add a PPPIOCGL2TPSTATS ioctl to allow userspace to obtain
L2TP counters and state from the kernel.

Add new if_pppol2tp.h header.

[ Modified to use aligned_u64 in statistics structure -DaveM ]

Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 101 insertions, 2 deletions

diff --git a/include/linux/Kbuild b/include/linux/Kbuild
index d94451682761..127d2d192b5a 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -225,6 +225,7 @@ unifdef-y += if_fddi.h
 unifdef-y += if_frad.h
 unifdef-y += if_ltalk.h
 unifdef-y += if_link.h
+unifdef-y += if_pppol2tp.h
 unifdef-y += if_pppox.h
 unifdef-y += if_shaper.h
 unifdef-y += if_tr.h
diff --git a/include/linux/if_ppp.h b/include/linux/if_ppp.h
index 768372f07caa..0f2f70d4e48c 100644
--- a/include/linux/if_ppp.h
+++ b/include/linux/if_ppp.h
@@ -110,6 +110,21 @@ struct ifpppcstatsreq {
         struct ppp_comp_stats stats;
 };
 
+/* For PPPIOCGL2TPSTATS */
+struct pppol2tp_ioc_stats {
+        __u16           tunnel_id;      /* redundant */
+        __u16           session_id;     /* if zero, get tunnel stats */
+        __u32           using_ipsec:1;  /* valid only for session_id == 0 */
+        aligned_u64     tx_packets;
+        aligned_u64     tx_bytes;
+        aligned_u64     tx_errors;
+        aligned_u64     rx_packets;
+        aligned_u64     rx_bytes;
+        aligned_u64     rx_seq_discards;
+        aligned_u64     rx_oos_packets;
+        aligned_u64     rx_errors;
+};
+
 #define ifr__name       b.ifr_ifrn.ifrn_name
 #define stats_ptr       b.ifr_ifru.ifru_data
 
@@ -146,6 +161,7 @@ struct ifpppcstatsreq {
 #define PPPIOCDISCONN   _IO('t', 57)            /* disconnect channel */
 #define PPPIOCATTCHAN   _IOW('t', 56, int)      /* attach to ppp channel */
 #define PPPIOCGCHAN     _IOR('t', 55, int)      /* get ppp channel number */
+#define PPPIOCGL2TPSTATS _IOR('t', 54, struct pppol2tp_ioc_stats)
 
 #define SIOCGPPPSTATS   (SIOCDEVPRIVATE + 0)
 #define SIOCGPPPVER     (SIOCDEVPRIVATE + 1)    /* NEVER change this!! */
diff --git a/include/linux/if_pppol2tp.h b/include/linux/if_pppol2tp.h
new file mode 100644
index 000000000000..516203b6fdeb
--- /dev/null
+++ b/include/linux/if_pppol2tp.h
@@ -0,0 +1,69 @@
+/***************************************************************************
+ * Linux PPP over L2TP (PPPoL2TP) Socket Implementation (RFC 2661)
+ *
+ * This file supplies definitions required by the PPP over L2TP driver
+ * (pppol2tp.c).  All version information wrt this file is located in pppol2tp.c
+ *
+ * License:
+ *              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.
+ *
+ */
+
+#ifndef __LINUX_IF_PPPOL2TP_H
+#define __LINUX_IF_PPPOL2TP_H
+
+#include <asm/types.h>
+
+#ifdef __KERNEL__
+#include <linux/in.h>
+#endif
+
+/* Structure used to connect() the socket to a particular tunnel UDP
+ * socket.
+ */
+struct pppol2tp_addr
+{
+        pid_t   pid;                    /* pid that owns the fd.
+                                         * 0 => current */
+        int     fd;                     /* FD of UDP socket to use */
+
+        struct sockaddr_in addr;        /* IP address and port to send to */
+
+        __be16 s_tunnel, s_session;     /* For matching incoming packets */
+        __be16 d_tunnel, d_session;     /* For sending outgoing packets */
+};
+
+/* Socket options:
+ * DEBUG        - bitmask of debug message categories
+ * SENDSEQ      - 0 => don't send packets with sequence numbers
+ *                1 => send packets with sequence numbers
+ * RECVSEQ      - 0 => receive packet sequence numbers are optional
+ *                1 => drop receive packets without sequence numbers
+ * LNSMODE      - 0 => act as LAC.
+ *                1 => act as LNS.
+ * REORDERTO    - reorder timeout (in millisecs). If 0, don't try to reorder.
+ */
+enum {
+        PPPOL2TP_SO_DEBUG       = 1,
+        PPPOL2TP_SO_RECVSEQ     = 2,
+        PPPOL2TP_SO_SENDSEQ     = 3,
+        PPPOL2TP_SO_LNSMODE     = 4,
+        PPPOL2TP_SO_REORDERTO   = 5,
+};
+
+/* Debug message categories for the DEBUG socket option */
+enum {
+        PPPOL2TP_MSG_DEBUG      = (1 << 0),     /* verbose debug (if
+                                                 * compiled in) */
+        PPPOL2TP_MSG_CONTROL    = (1 << 1),     /* userspace - kernel
+                                                 * interface */
+        PPPOL2TP_MSG_SEQ        = (1 << 2),     /* sequence numbers */
+        PPPOL2TP_MSG_DATA       = (1 << 3),     /* data packets */
+};
+
+
+
+#endif
diff --git a/include/linux/if_pppox.h b/include/linux/if_pppox.h
index 6f987be60fe2..25652545ba6e 100644
--- a/include/linux/if_pppox.h
+++ b/include/linux/if_pppox.h
@@ -27,6 +27,7 @@
 #include <asm/semaphore.h>
 #include <linux/ppp_channel.h>
 #endif /* __KERNEL__ */
+#include <linux/if_pppol2tp.h>
 
 /* For user-space programs to pick up these definitions
  * which they wouldn't get otherwise without defining __KERNEL__
@@ -50,8 +51,9 @@ struct pppoe_addr{
  * Protocols supported by AF_PPPOX 
  */ 
 #define PX_PROTO_OE    0 /* Currently just PPPoE */
-#define PX_MAX_PROTO   1        
- 
+#define PX_PROTO_OL2TP 1 /* Now L2TP also */
+#define PX_MAX_PROTO   2
+
 struct sockaddr_pppox { 
        sa_family_t     sa_family;            /* address family, AF_PPPOX */ 
        unsigned int    sa_protocol;          /* protocol identifier */ 
@@ -60,6 +62,16 @@ struct sockaddr_pppox {
        }sa_addr; 
 }__attribute__ ((packed)); 
 
+/* The use of the above union isn't viable because the size of this
+ * struct must stay fixed over time -- applications use sizeof(struct
+ * sockaddr_pppox) to fill it. We use a protocol specific sockaddr
+ * type instead.
+ */
+struct sockaddr_pppol2tp {
+        sa_family_t     sa_family;      /* address family, AF_PPPOX */
+        unsigned int    sa_protocol;    /* protocol identifier */
+        struct pppol2tp_addr pppol2tp;
+}__attribute__ ((packed));
 
 /*********************************************************************
  *
diff --git a/include/linux/socket.h b/include/linux/socket.h
index 6e7c9483a6a6..fe195c97a89d 100644
--- a/include/linux/socket.h
+++ b/include/linux/socket.h
@@ -287,6 +287,7 @@ struct ucred {
 #define SOL_NETLINK     270
 #define SOL_TIPC        271
 #define SOL_RXRPC       272
+#define SOL_PPPOL2TP    273
 
 /* IPX options */
 #define IPX_TYPE        1