1412 lines
40 KiB
C
1412 lines
40 KiB
C
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/*
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* ng_ppp.c
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*
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* Copyright (c) 1996-1999 Whistle Communications, Inc.
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* All rights reserved.
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*
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* Subject to the following obligations and disclaimer of warranty, use and
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* redistribution of this software, in source or object code forms, with or
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* without modifications are expressly permitted by Whistle Communications;
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* provided, however, that:
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* 1. Any and all reproductions of the source or object code must include the
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* copyright notice above and the following disclaimer of warranties; and
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* 2. No rights are granted, in any manner or form, to use Whistle
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* Communications, Inc. trademarks, including the mark "WHISTLE
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* COMMUNICATIONS" on advertising, endorsements, or otherwise except as
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* such appears in the above copyright notice or in the software.
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*
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* THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
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* TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
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* REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
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* INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
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* WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
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* REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
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* SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
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* IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
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* RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
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* WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
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* PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
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* SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
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* OF SUCH DAMAGE.
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*
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* Author: Archie Cobbs <archie@whistle.com>
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*
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* $FreeBSD$
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* $Whistle: ng_ppp.c,v 1.24 1999/11/01 09:24:52 julian Exp $
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*/
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/*
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* PPP node type.
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*/
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/kernel.h>
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#include <sys/conf.h>
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#include <sys/mbuf.h>
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#include <sys/malloc.h>
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#include <sys/errno.h>
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#include <sys/socket.h>
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#include <sys/syslog.h>
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#include <netgraph/ng_message.h>
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#include <netgraph/netgraph.h>
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#include <netgraph/ng_ppp.h>
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#include <netgraph/ng_vjc.h>
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#define PROT_VALID(p) (((p) & 0x0101) == 0x0001)
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#define PROT_COMPRESSABLE(p) (((p) & 0xff00) == 0x0000)
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/* Some PPP protocol numbers we're interested in */
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#define PROT_APPLETALK 0x0029
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#define PROT_COMPD 0x00fd
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#define PROT_CRYPTD 0x0053
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#define PROT_IP 0x0021
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#define PROT_IPX 0x002b
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#define PROT_MP 0x003d
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#define PROT_VJCOMP 0x002d
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#define PROT_VJUNCOMP 0x002f
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/* Multilink PPP definitions */
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#define MP_MIN_MRRU 1500 /* per RFC 1990 */
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#define MP_INITIAL_SEQ 0 /* per RFC 1990 */
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#define MP_MIN_LINK_MRU 32
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#define MP_MAX_SEQ_LINGER 64 /* max frags we will hold */
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#define MP_INSANE_SEQ_JUMP 128 /* a sequence # jump too far */
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#define MP_MIN_FRAG_LEN 6 /* don't frag smaller frames */
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#define MP_SHORT_SEQ_MASK 0x00000fff /* short seq # mask */
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#define MP_SHORT_SEQ_HIBIT 0x00000800 /* short seq # high bit */
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#define MP_SHORT_FIRST_FLAG 0x00008000 /* first fragment in frame */
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#define MP_SHORT_LAST_FLAG 0x00004000 /* last fragment in frame */
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#define MP_LONG_SEQ_MASK 0x00ffffff /* long seq # mask */
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#define MP_LONG_SEQ_HIBIT 0x00800000 /* long seq # high bit */
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#define MP_LONG_FIRST_FLAG 0x80000000 /* first fragment in frame */
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#define MP_LONG_LAST_FLAG 0x40000000 /* last fragment in frame */
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#define MP_SEQ_MASK (priv->conf.recvShortSeq ? \
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MP_SHORT_SEQ_MASK : MP_LONG_SEQ_MASK)
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/* Sign extension of MP sequence numbers */
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#define MP_SHORT_EXTEND(s) (((s) & MP_SHORT_SEQ_HIBIT) ? \
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((s) | ~MP_SHORT_SEQ_MASK) : (s))
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#define MP_LONG_EXTEND(s) (((s) & MP_LONG_SEQ_HIBIT) ? \
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((s) | ~MP_LONG_SEQ_MASK) : (s))
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/* Comparision of MP sequence numbers */
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#define MP_SHORT_SEQ_DIFF(x,y) (MP_SHORT_EXTEND(x) - MP_SHORT_EXTEND(y))
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#define MP_LONG_SEQ_DIFF(x,y) (MP_LONG_EXTEND(x) - MP_LONG_EXTEND(y))
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#define MP_SEQ_DIFF(x,y) (priv->conf.recvShortSeq ? \
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MP_SHORT_SEQ_DIFF((x), (y)) : \
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MP_LONG_SEQ_DIFF((x), (y)))
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/* We store incoming fragments this way */
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struct ng_ppp_frag {
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int seq;
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u_char first;
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u_char last;
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struct mbuf *data;
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meta_p meta;
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CIRCLEQ_ENTRY(ng_ppp_frag) f_qent;
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};
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/* We keep track of link queue status this way */
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struct ng_ppp_link_qstat {
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struct timeval lastWrite; /* time of last write */
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int bytesInQueue; /* bytes in the queue then */
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};
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/* We use integer indicies to refer to the non-link hooks */
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static const char *const ng_ppp_hook_names[] = {
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NG_PPP_HOOK_ATALK,
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#define HOOK_INDEX_ATALK 0
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NG_PPP_HOOK_BYPASS,
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#define HOOK_INDEX_BYPASS 1
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NG_PPP_HOOK_COMPRESS,
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#define HOOK_INDEX_COMPRESS 2
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NG_PPP_HOOK_ENCRYPT,
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#define HOOK_INDEX_ENCRYPT 3
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NG_PPP_HOOK_DECOMPRESS,
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#define HOOK_INDEX_DECOMPRESS 4
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NG_PPP_HOOK_DECRYPT,
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#define HOOK_INDEX_DECRYPT 5
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NG_PPP_HOOK_INET,
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#define HOOK_INDEX_INET 6
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NG_PPP_HOOK_IPX,
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#define HOOK_INDEX_IPX 7
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NG_PPP_HOOK_VJC_COMP,
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#define HOOK_INDEX_VJC_COMP 8
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NG_PPP_HOOK_VJC_IP,
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#define HOOK_INDEX_VJC_IP 9
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NG_PPP_HOOK_VJC_UNCOMP,
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#define HOOK_INDEX_VJC_UNCOMP 10
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NG_PPP_HOOK_VJC_VJIP,
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#define HOOK_INDEX_VJC_VJIP 11
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NULL
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#define HOOK_INDEX_MAX 12
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};
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/* We store index numbers in the hook private pointer. The HOOK_INDEX()
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for a hook is either the index (above) for normal hooks, or the ones
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complement of the link number for link hooks. */
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#define HOOK_INDEX(hook) (*((int16_t *) &(hook)->private))
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/* Node private data */
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struct private {
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struct ng_ppp_node_config conf;
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struct ng_ppp_link_stat bundleStats;
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struct ng_ppp_link_stat linkStats[NG_PPP_MAX_LINKS];
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hook_p links[NG_PPP_MAX_LINKS];
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hook_p hooks[HOOK_INDEX_MAX];
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u_char vjCompHooked;
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u_char allLinksEqual;
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u_short activeLinks[NG_PPP_MAX_LINKS];
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u_int numActiveLinks;
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u_int lastLink; /* for round robin */
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struct ng_ppp_link_qstat qstat[NG_PPP_MAX_LINKS];
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CIRCLEQ_HEAD(ng_ppp_fraglist, ng_ppp_frag)
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frags; /* incoming fragments */
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int mpSeqOut; /* next out MP seq # */
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};
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typedef struct private *priv_p;
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/* Netgraph node methods */
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static ng_constructor_t ng_ppp_constructor;
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static ng_rcvmsg_t ng_ppp_rcvmsg;
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static ng_shutdown_t ng_ppp_rmnode;
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static ng_newhook_t ng_ppp_newhook;
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static ng_rcvdata_t ng_ppp_rcvdata;
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static ng_disconnect_t ng_ppp_disconnect;
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/* Helper functions */
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static int ng_ppp_input(node_p node, int ln, struct mbuf *m, meta_p meta);
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static int ng_ppp_output(node_p node, int ln, struct mbuf *m, meta_p meta);
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static int ng_ppp_mp_input(node_p nd, int ln, struct mbuf *m, meta_p meta);
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static int ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta);
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static void ng_ppp_mp_strategy(node_p node, int len, int *distrib);
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static int ng_ppp_intcmp(const void *v1, const void *v2);
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static struct mbuf *ng_ppp_addproto(struct mbuf *m, int proto, int compOK);
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static int ng_ppp_config_valid(node_p node,
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const struct ng_ppp_node_config *newConf);
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static void ng_ppp_update(node_p node, int newConf);
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static void ng_ppp_free_frags(node_p node);
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/* Node type descriptor */
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static struct ng_type ng_ppp_typestruct = {
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NG_VERSION,
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NG_PPP_NODE_TYPE,
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NULL,
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ng_ppp_constructor,
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ng_ppp_rcvmsg,
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ng_ppp_rmnode,
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ng_ppp_newhook,
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NULL,
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NULL,
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ng_ppp_rcvdata,
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ng_ppp_rcvdata,
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ng_ppp_disconnect
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};
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NETGRAPH_INIT(ppp, &ng_ppp_typestruct);
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static int *compareLatencies; /* hack for ng_ppp_intcmp() */
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#define ERROUT(x) do { error = (x); goto done; } while (0)
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/************************************************************************
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NETGRAPH NODE STUFF
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************************************************************************/
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/*
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* Node type constructor
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*/
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static int
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ng_ppp_constructor(node_p *nodep)
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{
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priv_p priv;
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int error;
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/* Allocate private structure */
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MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_WAITOK);
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if (priv == NULL)
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return (ENOMEM);
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bzero(priv, sizeof(*priv));
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/* Call generic node constructor */
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if ((error = ng_make_node_common(&ng_ppp_typestruct, nodep))) {
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FREE(priv, M_NETGRAPH);
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return (error);
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}
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(*nodep)->private = priv;
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/* Initialize state */
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CIRCLEQ_INIT(&priv->frags);
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/* Done */
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return (0);
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}
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/*
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* Give our OK for a hook to be added
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*/
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static int
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ng_ppp_newhook(node_p node, hook_p hook, const char *name)
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{
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const priv_p priv = node->private;
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int linkNum = -1;
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hook_p *hookPtr = NULL;
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int hookIndex = -1;
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/* Figure out which hook it is */
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if (strncmp(name, NG_PPP_HOOK_LINK_PREFIX, /* a link hook? */
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strlen(NG_PPP_HOOK_LINK_PREFIX)) == 0) {
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const char *cp, *eptr;
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cp = name + strlen(NG_PPP_HOOK_LINK_PREFIX);
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if (!isdigit(*cp) || (cp[0] == '0' && cp[1] != '\0'))
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return (EINVAL);
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linkNum = (int)strtoul(cp, &eptr, 10);
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if (*eptr != '\0' || linkNum < 0 || linkNum >= NG_PPP_MAX_LINKS)
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return (EINVAL);
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hookPtr = &priv->links[linkNum];
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hookIndex = ~linkNum;
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} else { /* must be a non-link hook */
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int i;
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for (i = 0; ng_ppp_hook_names[i] != NULL; i++) {
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if (strcmp(name, ng_ppp_hook_names[i]) == 0) {
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hookPtr = &priv->hooks[i];
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hookIndex = i;
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break;
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}
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}
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if (ng_ppp_hook_names[i] == NULL)
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return (EINVAL); /* no such hook */
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}
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/* See if hook is already connected */
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if (*hookPtr != NULL)
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return (EISCONN);
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/* Disallow more than one link unless multilink is enabled */
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if (linkNum != -1 && priv->conf.links[linkNum].enableLink
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&& !priv->conf.enableMultilink && priv->numActiveLinks >= 1)
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return (ENODEV);
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/* OK */
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*hookPtr = hook;
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HOOK_INDEX(hook) = hookIndex;
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ng_ppp_update(node, 0);
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return (0);
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}
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/*
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* Receive a control message
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*/
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static int
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ng_ppp_rcvmsg(node_p node, struct ng_mesg *msg,
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const char *raddr, struct ng_mesg **rptr)
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{
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const priv_p priv = node->private;
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struct ng_mesg *resp = NULL;
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int error = 0;
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switch (msg->header.typecookie) {
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case NGM_PPP_COOKIE:
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switch (msg->header.cmd) {
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case NGM_PPP_SET_CONFIG:
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{
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struct ng_ppp_node_config *const newConf =
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(struct ng_ppp_node_config *) msg->data;
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/* Check for invalid or illegal config */
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if (msg->header.arglen != sizeof(*newConf))
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ERROUT(EINVAL);
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if (!ng_ppp_config_valid(node, newConf))
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ERROUT(EINVAL);
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priv->conf = *newConf;
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ng_ppp_update(node, 1);
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break;
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}
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case NGM_PPP_GET_CONFIG:
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NG_MKRESPONSE(resp, msg, sizeof(priv->conf), M_NOWAIT);
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if (resp == NULL)
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ERROUT(ENOMEM);
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bcopy(&priv->conf, resp->data, sizeof(priv->conf));
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break;
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case NGM_PPP_GET_LINK_STATS:
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case NGM_PPP_CLR_LINK_STATS:
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{
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struct ng_ppp_link_stat *stats;
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u_int16_t linkNum;
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if (msg->header.arglen != sizeof(u_int16_t))
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ERROUT(EINVAL);
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linkNum = *((u_int16_t *) msg->data);
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if (linkNum >= NG_PPP_MAX_LINKS
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&& linkNum != NG_PPP_BUNDLE_LINKNUM)
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ERROUT(EINVAL);
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stats = (linkNum == NG_PPP_BUNDLE_LINKNUM) ?
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&priv->bundleStats : &priv->linkStats[linkNum];
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if (msg->header.cmd == NGM_PPP_GET_LINK_STATS) {
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NG_MKRESPONSE(resp, msg,
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sizeof(struct ng_ppp_link_stat), M_NOWAIT);
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if (resp == NULL)
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ERROUT(ENOMEM);
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bcopy(stats, resp->data, sizeof(*stats));
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} else
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bzero(stats, sizeof(*stats));
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break;
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}
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default:
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error = EINVAL;
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break;
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}
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break;
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case NGM_VJC_COOKIE:
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{
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char path[NG_PATHLEN + 1];
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node_p origNode;
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if ((error = ng_path2node(node, raddr, &origNode, NULL)) != 0)
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ERROUT(error);
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snprintf(path, sizeof(path), "[%lx]:%s",
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(long) node, NG_PPP_HOOK_VJC_IP);
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return ng_send_msg(origNode, msg, path, rptr);
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break;
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}
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default:
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error = EINVAL;
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break;
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}
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if (rptr)
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*rptr = resp;
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else if (resp)
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FREE(resp, M_NETGRAPH);
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done:
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FREE(msg, M_NETGRAPH);
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return (error);
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}
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|
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/*
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* Receive data on a hook
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*/
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static int
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ng_ppp_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
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{
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const node_p node = hook->node;
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const priv_p priv = node->private;
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const int index = HOOK_INDEX(hook);
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u_int16_t linkNum = NG_PPP_BUNDLE_LINKNUM;
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hook_p outHook = NULL;
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int proto = 0, error;
|
|
|
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/* Did it come from a link hook? */
|
|
if (index < 0) {
|
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|
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/* Is link active? */
|
|
linkNum = (u_int16_t)~index;
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KASSERT(linkNum < NG_PPP_MAX_LINKS,
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("%s: bogus index 0x%x", __FUNCTION__, index));
|
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if (!priv->conf.links[linkNum].enableLink) {
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NG_FREE_DATA(m, meta);
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return (ENXIO);
|
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}
|
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|
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/* Stats */
|
|
priv->linkStats[linkNum].recvFrames++;
|
|
priv->linkStats[linkNum].recvOctets += m->m_pkthdr.len;
|
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|
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/* Dispatch incoming frame */
|
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return ng_ppp_input(node, linkNum, m, meta);
|
|
}
|
|
|
|
/* Get protocol & check if data allowed from this hook */
|
|
switch (index) {
|
|
|
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/* Downwards flowing data */
|
|
case HOOK_INDEX_ATALK:
|
|
if (!priv->conf.enableAtalk) {
|
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NG_FREE_DATA(m, meta);
|
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return (ENXIO);
|
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}
|
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proto = PROT_APPLETALK;
|
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break;
|
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case HOOK_INDEX_IPX:
|
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if (!priv->conf.enableIPX) {
|
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NG_FREE_DATA(m, meta);
|
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return (ENXIO);
|
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}
|
|
proto = PROT_IPX;
|
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break;
|
|
case HOOK_INDEX_INET:
|
|
case HOOK_INDEX_VJC_VJIP:
|
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if (!priv->conf.enableIP) {
|
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NG_FREE_DATA(m, meta);
|
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return (ENXIO);
|
|
}
|
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proto = PROT_IP;
|
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break;
|
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case HOOK_INDEX_VJC_COMP:
|
|
if (!priv->conf.enableVJCompression) {
|
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NG_FREE_DATA(m, meta);
|
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return (ENXIO);
|
|
}
|
|
proto = PROT_VJCOMP;
|
|
break;
|
|
case HOOK_INDEX_VJC_UNCOMP:
|
|
if (!priv->conf.enableVJCompression) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENXIO);
|
|
}
|
|
proto = PROT_VJUNCOMP;
|
|
break;
|
|
case HOOK_INDEX_COMPRESS:
|
|
if (!priv->conf.enableCompression) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENXIO);
|
|
}
|
|
proto = PROT_COMPD;
|
|
break;
|
|
case HOOK_INDEX_ENCRYPT:
|
|
if (!priv->conf.enableEncryption) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENXIO);
|
|
}
|
|
proto = PROT_CRYPTD;
|
|
break;
|
|
case HOOK_INDEX_BYPASS:
|
|
if (m->m_pkthdr.len < 4) {
|
|
NG_FREE_META(meta);
|
|
return (EINVAL);
|
|
}
|
|
if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
linkNum = ntohs(mtod(m, u_int16_t *)[0]);
|
|
proto = ntohs(mtod(m, u_int16_t *)[1]);
|
|
m_adj(m, 4);
|
|
if (linkNum >= NG_PPP_MAX_LINKS
|
|
&& linkNum != NG_PPP_BUNDLE_LINKNUM)
|
|
return (EINVAL);
|
|
break;
|
|
|
|
/* Upwards flowing data */
|
|
case HOOK_INDEX_VJC_IP:
|
|
if (!priv->conf.enableVJDecompression) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENXIO);
|
|
}
|
|
break;
|
|
case HOOK_INDEX_DECOMPRESS:
|
|
if (!priv->conf.enableDecompression) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENXIO);
|
|
}
|
|
break;
|
|
case HOOK_INDEX_DECRYPT:
|
|
if (!priv->conf.enableDecryption) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENXIO);
|
|
}
|
|
break;
|
|
default:
|
|
KASSERT(0, ("%s: bogus index 0x%x", __FUNCTION__, index));
|
|
}
|
|
|
|
/* Now figure out what to do with the frame */
|
|
switch (index) {
|
|
case HOOK_INDEX_INET:
|
|
if (priv->conf.enableVJCompression && priv->vjCompHooked) {
|
|
outHook = priv->hooks[HOOK_INDEX_VJC_IP];
|
|
break;
|
|
}
|
|
/* FALLTHROUGH */
|
|
case HOOK_INDEX_ATALK:
|
|
case HOOK_INDEX_IPX:
|
|
case HOOK_INDEX_VJC_COMP:
|
|
case HOOK_INDEX_VJC_UNCOMP:
|
|
case HOOK_INDEX_VJC_VJIP:
|
|
if (priv->conf.enableCompression
|
|
&& priv->hooks[HOOK_INDEX_COMPRESS] != NULL) {
|
|
if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
outHook = priv->hooks[HOOK_INDEX_COMPRESS];
|
|
break;
|
|
}
|
|
/* FALLTHROUGH */
|
|
case HOOK_INDEX_COMPRESS:
|
|
if (priv->conf.enableEncryption
|
|
&& priv->hooks[HOOK_INDEX_ENCRYPT] != NULL) {
|
|
if ((m = ng_ppp_addproto(m, proto, 1)) == NULL) {
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
outHook = priv->hooks[HOOK_INDEX_ENCRYPT];
|
|
break;
|
|
}
|
|
/* FALLTHROUGH */
|
|
case HOOK_INDEX_ENCRYPT:
|
|
case HOOK_INDEX_BYPASS:
|
|
if ((m = ng_ppp_addproto(m, proto,
|
|
linkNum == NG_PPP_BUNDLE_LINKNUM
|
|
|| priv->conf.links[linkNum].enableProtoComp)) == NULL) {
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
return ng_ppp_output(node, NG_PPP_BUNDLE_LINKNUM, m, meta);
|
|
|
|
/* Incoming data */
|
|
case HOOK_INDEX_DECRYPT:
|
|
case HOOK_INDEX_DECOMPRESS:
|
|
case HOOK_INDEX_VJC_IP:
|
|
return ng_ppp_input(node, NG_PPP_BUNDLE_LINKNUM, m, meta);
|
|
}
|
|
|
|
/* Send packet out hook */
|
|
NG_SEND_DATA(error, outHook, m, meta);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Destroy node
|
|
*/
|
|
static int
|
|
ng_ppp_rmnode(node_p node)
|
|
{
|
|
const priv_p priv = node->private;
|
|
|
|
/* Take down netgraph node */
|
|
node->flags |= NG_INVALID;
|
|
ng_cutlinks(node);
|
|
ng_unname(node);
|
|
bzero(priv, sizeof(*priv));
|
|
FREE(priv, M_NETGRAPH);
|
|
node->private = NULL;
|
|
ng_unref(node); /* let the node escape */
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Hook disconnection
|
|
*/
|
|
static int
|
|
ng_ppp_disconnect(hook_p hook)
|
|
{
|
|
if (hook->node->numhooks == 0)
|
|
ng_rmnode(hook->node);
|
|
return (0);
|
|
}
|
|
|
|
/************************************************************************
|
|
HELPER STUFF
|
|
************************************************************************/
|
|
|
|
/*
|
|
* Handle an incoming frame. Extract the PPP protocol number
|
|
* and dispatch accordingly.
|
|
*/
|
|
static int
|
|
ng_ppp_input(node_p node, int linkNum, struct mbuf *m, meta_p meta)
|
|
{
|
|
const priv_p priv = node->private;
|
|
hook_p outHook = NULL;
|
|
int proto, error;
|
|
|
|
/* Extract protocol number */
|
|
for (proto = 0; !PROT_VALID(proto) && m->m_pkthdr.len > 0; ) {
|
|
if (m->m_len < 1 && (m = m_pullup(m, 1)) == NULL) {
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
proto = (proto << 8) + *mtod(m, u_char *);
|
|
m_adj(m, 1);
|
|
}
|
|
if (!PROT_VALID(proto)) {
|
|
if (linkNum == NG_PPP_BUNDLE_LINKNUM)
|
|
priv->bundleStats.badProtos++;
|
|
else
|
|
priv->linkStats[linkNum].badProtos++;
|
|
NG_FREE_DATA(m, meta);
|
|
return (EINVAL);
|
|
}
|
|
|
|
/* Check protocol */
|
|
switch (proto) {
|
|
case PROT_COMPD:
|
|
if (priv->conf.enableDecompression)
|
|
outHook = priv->hooks[HOOK_INDEX_DECOMPRESS];
|
|
break;
|
|
case PROT_CRYPTD:
|
|
if (priv->conf.enableDecryption)
|
|
outHook = priv->hooks[HOOK_INDEX_DECRYPT];
|
|
break;
|
|
case PROT_VJCOMP:
|
|
if (priv->conf.enableVJDecompression && priv->vjCompHooked)
|
|
outHook = priv->hooks[HOOK_INDEX_VJC_COMP];
|
|
break;
|
|
case PROT_VJUNCOMP:
|
|
if (priv->conf.enableVJDecompression && priv->vjCompHooked)
|
|
outHook = priv->hooks[HOOK_INDEX_VJC_UNCOMP];
|
|
break;
|
|
case PROT_MP:
|
|
if (priv->conf.enableMultilink) {
|
|
NG_FREE_META(meta);
|
|
return ng_ppp_mp_input(node, linkNum, m, meta);
|
|
}
|
|
break;
|
|
case PROT_APPLETALK:
|
|
if (priv->conf.enableAtalk)
|
|
outHook = priv->hooks[HOOK_INDEX_ATALK];
|
|
break;
|
|
case PROT_IPX:
|
|
if (priv->conf.enableIPX)
|
|
outHook = priv->hooks[HOOK_INDEX_IPX];
|
|
break;
|
|
case PROT_IP:
|
|
if (priv->conf.enableIP)
|
|
outHook = priv->hooks[HOOK_INDEX_INET];
|
|
break;
|
|
}
|
|
|
|
/* For unknown/inactive protocols, forward out the bypass hook */
|
|
if (outHook == NULL) {
|
|
M_PREPEND(m, 4, M_NOWAIT);
|
|
if (m == NULL || (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL))
|
|
return (ENOBUFS);
|
|
mtod(m, u_int16_t *)[0] = htons(linkNum);
|
|
mtod(m, u_int16_t *)[1] = htons(proto);
|
|
outHook = priv->hooks[HOOK_INDEX_BYPASS];
|
|
}
|
|
|
|
/* Forward frame */
|
|
NG_SEND_DATA(error, outHook, m, meta);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Deliver a frame out a link, either a real one or NG_PPP_BUNDLE_LINKNUM
|
|
*/
|
|
static int
|
|
ng_ppp_output(node_p node, int linkNum, struct mbuf *m, meta_p meta)
|
|
{
|
|
const priv_p priv = node->private;
|
|
int error;
|
|
|
|
/* Check for bundle virtual link */
|
|
if (linkNum == NG_PPP_BUNDLE_LINKNUM) {
|
|
if (priv->conf.enableMultilink)
|
|
return ng_ppp_mp_output(node, m, meta);
|
|
linkNum = priv->activeLinks[0];
|
|
}
|
|
|
|
/* Check link status */
|
|
if (!priv->conf.links[linkNum].enableLink)
|
|
return (ENXIO);
|
|
if (priv->links[linkNum] == NULL) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENETDOWN);
|
|
}
|
|
|
|
/* Deliver frame */
|
|
NG_SEND_DATA(error, priv->links[linkNum], m, meta);
|
|
|
|
/* Update stats and 'bytes in queue' counter */
|
|
if (error == 0) {
|
|
priv->linkStats[linkNum].xmitFrames++;
|
|
priv->linkStats[linkNum].xmitOctets += m->m_pkthdr.len;
|
|
priv->qstat[linkNum].bytesInQueue += m->m_pkthdr.len;
|
|
microtime(&priv->qstat[linkNum].lastWrite);
|
|
}
|
|
return error;
|
|
}
|
|
|
|
/*
|
|
* Handle an incoming multi-link fragment
|
|
*/
|
|
static int
|
|
ng_ppp_mp_input(node_p node, int linkNum, struct mbuf *m, meta_p meta)
|
|
{
|
|
const priv_p priv = node->private;
|
|
struct ng_ppp_frag frag0, *frag = &frag0;
|
|
struct ng_ppp_frag *qent, *qnext;
|
|
struct ng_ppp_frag *first = NULL, *last = NULL;
|
|
int diff, highSeq, nextSeq;
|
|
struct mbuf *tail;
|
|
|
|
/* Extract fragment information from MP header */
|
|
if (priv->conf.recvShortSeq) {
|
|
u_int16_t shdr;
|
|
|
|
if (m->m_pkthdr.len < 2) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (EINVAL);
|
|
}
|
|
if (m->m_len < 2 && (m = m_pullup(m, 2)) == NULL) {
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
shdr = ntohs(*mtod(m, u_int16_t *));
|
|
frag->seq = shdr & MP_SHORT_SEQ_MASK;
|
|
frag->first = (shdr & MP_SHORT_FIRST_FLAG) != 0;
|
|
frag->last = (shdr & MP_SHORT_LAST_FLAG) != 0;
|
|
highSeq = CIRCLEQ_EMPTY(&priv->frags) ?
|
|
frag->seq : CIRCLEQ_FIRST(&priv->frags)->seq;
|
|
diff = MP_SHORT_SEQ_DIFF(frag->seq, highSeq);
|
|
m_adj(m, 2);
|
|
} else {
|
|
u_int32_t lhdr;
|
|
|
|
if (m->m_pkthdr.len < 4) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (EINVAL);
|
|
}
|
|
if (m->m_len < 4 && (m = m_pullup(m, 4)) == NULL) {
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
lhdr = ntohl(*mtod(m, u_int32_t *));
|
|
frag->seq = lhdr & MP_LONG_SEQ_MASK;
|
|
frag->first = (lhdr & MP_LONG_FIRST_FLAG) != 0;
|
|
frag->last = (lhdr & MP_LONG_LAST_FLAG) != 0;
|
|
highSeq = CIRCLEQ_EMPTY(&priv->frags) ?
|
|
frag->seq : CIRCLEQ_FIRST(&priv->frags)->seq;
|
|
diff = MP_LONG_SEQ_DIFF(frag->seq, highSeq);
|
|
m_adj(m, 4);
|
|
}
|
|
frag->data = m;
|
|
frag->meta = meta;
|
|
|
|
/* If the sequence number makes a large jump, empty the queue */
|
|
if (diff <= -MP_INSANE_SEQ_JUMP || diff >= MP_INSANE_SEQ_JUMP)
|
|
ng_ppp_free_frags(node);
|
|
|
|
/* Optimization: handle a frame that's all in one fragment */
|
|
if (frag->first && frag->last)
|
|
return ng_ppp_input(node, NG_PPP_BUNDLE_LINKNUM, m, meta);
|
|
|
|
/* Allocate a new frag struct for the queue */
|
|
MALLOC(frag, struct ng_ppp_frag *, sizeof(*frag), M_NETGRAPH, M_NOWAIT);
|
|
if (frag == NULL) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENOMEM);
|
|
}
|
|
*frag = frag0;
|
|
meta = NULL;
|
|
m = NULL;
|
|
|
|
/* Add fragment to queue, which is reverse sorted by sequence number */
|
|
CIRCLEQ_FOREACH(qent, &priv->frags, f_qent) {
|
|
diff = MP_SEQ_DIFF(frag->seq, qent->seq);
|
|
if (diff > 0) {
|
|
CIRCLEQ_INSERT_BEFORE(&priv->frags, qent, frag, f_qent);
|
|
break;
|
|
} else if (diff == 0) { /* should never happen! */
|
|
log(LOG_ERR, "%s: rec'd dup MP fragment\n", node->name);
|
|
if (linkNum == NG_PPP_BUNDLE_LINKNUM)
|
|
priv->linkStats[linkNum].dupFragments++;
|
|
else
|
|
priv->bundleStats.dupFragments++;
|
|
NG_FREE_DATA(frag->data, frag->meta);
|
|
FREE(frag, M_NETGRAPH);
|
|
return (EINVAL);
|
|
}
|
|
}
|
|
if (qent == NULL)
|
|
CIRCLEQ_INSERT_TAIL(&priv->frags, frag, f_qent);
|
|
|
|
/* Find the first fragment in the possibly newly completed frame */
|
|
for (nextSeq = frag->seq, qent = frag;
|
|
qent != (void *) &priv->frags;
|
|
qent = CIRCLEQ_PREV(qent, f_qent)) {
|
|
if (qent->seq != nextSeq)
|
|
goto pruneQueue;
|
|
if (qent->first) {
|
|
first = qent;
|
|
break;
|
|
}
|
|
nextSeq = (nextSeq + 1) & MP_SEQ_MASK;
|
|
}
|
|
|
|
/* Find the last fragment in the possibly newly completed frame */
|
|
for (nextSeq = frag->seq, qent = frag;
|
|
qent != (void *) &priv->frags;
|
|
qent = CIRCLEQ_NEXT(qent, f_qent)) {
|
|
if (qent->seq != nextSeq)
|
|
goto pruneQueue;
|
|
if (qent->last) {
|
|
last = qent;
|
|
break;
|
|
}
|
|
nextSeq = (nextSeq - 1) & MP_SEQ_MASK;
|
|
}
|
|
|
|
/* We have a complete frame, extract it from the queue */
|
|
for (tail = NULL, qent = first; qent != NULL; qent = qnext) {
|
|
qnext = CIRCLEQ_PREV(qent, f_qent);
|
|
CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
|
|
if (tail == NULL) {
|
|
tail = m = qent->data;
|
|
meta = qent->meta; /* inherit first frag's meta */
|
|
} else {
|
|
m->m_pkthdr.len += qent->data->m_pkthdr.len;
|
|
tail->m_next = qent->data;
|
|
NG_FREE_META(qent->meta); /* drop other frag's metas */
|
|
}
|
|
while (tail->m_next != NULL)
|
|
tail = tail->m_next;
|
|
if (qent == last)
|
|
qnext = NULL;
|
|
FREE(qent, M_NETGRAPH);
|
|
}
|
|
|
|
pruneQueue:
|
|
/* Prune out stale entries in the queue */
|
|
for (qent = CIRCLEQ_LAST(&priv->frags);
|
|
qent != (void *) &priv->frags; qent = qnext) {
|
|
if (MP_SEQ_DIFF(highSeq, qent->seq) <= MP_MAX_SEQ_LINGER)
|
|
break;
|
|
qnext = CIRCLEQ_PREV(qent, f_qent);
|
|
CIRCLEQ_REMOVE(&priv->frags, qent, f_qent);
|
|
NG_FREE_DATA(qent->data, qent->meta);
|
|
FREE(qent, M_NETGRAPH);
|
|
}
|
|
|
|
/* Deliver newly completed frame, if any */
|
|
return m ? ng_ppp_input(node, NG_PPP_BUNDLE_LINKNUM, m, meta) : 0;
|
|
}
|
|
|
|
/*
|
|
* Deliver a frame out on the bundle, i.e., figure out how to fragment
|
|
* the frame across the individual PPP links and do so.
|
|
*/
|
|
static int
|
|
ng_ppp_mp_output(node_p node, struct mbuf *m, meta_p meta)
|
|
{
|
|
const priv_p priv = node->private;
|
|
int distrib[NG_PPP_MAX_LINKS];
|
|
int firstFragment;
|
|
int activeLinkNum;
|
|
|
|
/* At least one link must be active */
|
|
if (priv->numActiveLinks == 0) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENETDOWN);
|
|
}
|
|
|
|
/* Round-robin strategy */
|
|
if (priv->conf.enableRoundRobin || m->m_pkthdr.len < MP_MIN_FRAG_LEN) {
|
|
activeLinkNum = priv->lastLink++ % priv->numActiveLinks;
|
|
bzero(&distrib, priv->numActiveLinks * sizeof(distrib[0]));
|
|
distrib[activeLinkNum] = m->m_pkthdr.len;
|
|
goto deliver;
|
|
}
|
|
|
|
/* Strategy when all links are equivalent (optimize the common case) */
|
|
if (priv->allLinksEqual) {
|
|
const int fraction = m->m_pkthdr.len / priv->numActiveLinks;
|
|
int i, remain;
|
|
|
|
for (i = 0; i < priv->numActiveLinks; i++)
|
|
distrib[priv->lastLink++ % priv->numActiveLinks]
|
|
= fraction;
|
|
remain = m->m_pkthdr.len - (fraction * priv->numActiveLinks);
|
|
while (remain > 0) {
|
|
distrib[priv->lastLink++ % priv->numActiveLinks]++;
|
|
remain--;
|
|
}
|
|
goto deliver;
|
|
}
|
|
|
|
/* Strategy when all links are not equivalent */
|
|
ng_ppp_mp_strategy(node, m->m_pkthdr.len, distrib);
|
|
|
|
deliver:
|
|
/* Update stats */
|
|
priv->bundleStats.xmitFrames++;
|
|
priv->bundleStats.xmitOctets += m->m_pkthdr.len;
|
|
|
|
/* Send alloted portions of frame out on the link(s) */
|
|
for (firstFragment = 1, activeLinkNum = priv->numActiveLinks - 1;
|
|
activeLinkNum >= 0; activeLinkNum--) {
|
|
const int linkNum = priv->activeLinks[activeLinkNum];
|
|
|
|
/* Deliver fragment(s) out the next link */
|
|
for ( ; distrib[activeLinkNum] > 0; firstFragment = 0) {
|
|
int len, lastFragment, error;
|
|
struct mbuf *m2;
|
|
meta_p meta2;
|
|
|
|
/* Calculate fragment length; don't exceed link MTU */
|
|
len = distrib[activeLinkNum];
|
|
if (len > priv->conf.links[linkNum].mru)
|
|
len = priv->conf.links[linkNum].mru;
|
|
distrib[activeLinkNum] -= len;
|
|
lastFragment = (len == m->m_pkthdr.len);
|
|
|
|
/* Split off next fragment as "m2" */
|
|
m2 = m;
|
|
if (!lastFragment) {
|
|
struct mbuf *n = m_split(m, len, M_NOWAIT);
|
|
|
|
if (n == NULL) {
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENOMEM);
|
|
}
|
|
m = n;
|
|
}
|
|
|
|
/* Prepend MP header */
|
|
if (priv->conf.xmitShortSeq) {
|
|
u_int16_t shdr;
|
|
|
|
M_PREPEND(m2, 2, M_NOWAIT);
|
|
if (m2 == NULL
|
|
|| (m2->m_len < 2
|
|
&& (m2 = m_pullup(m2, 2)) == NULL)) {
|
|
if (!lastFragment)
|
|
m_freem(m);
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
shdr = priv->mpSeqOut;
|
|
priv->mpSeqOut =
|
|
(priv->mpSeqOut + 1) % MP_SHORT_SEQ_MASK;
|
|
if (firstFragment)
|
|
shdr |= MP_SHORT_FIRST_FLAG;
|
|
if (lastFragment)
|
|
shdr |= MP_SHORT_LAST_FLAG;
|
|
*mtod(m2, u_int16_t *) = htons(shdr);
|
|
} else {
|
|
u_int32_t lhdr;
|
|
|
|
M_PREPEND(m2, 4, M_NOWAIT);
|
|
if (m2 == NULL
|
|
|| (m2->m_len < 4
|
|
&& (m2 = m_pullup(m2, 4)) == NULL)) {
|
|
if (!lastFragment)
|
|
m_freem(m);
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
lhdr = priv->mpSeqOut;
|
|
priv->mpSeqOut =
|
|
(priv->mpSeqOut + 1) % MP_LONG_SEQ_MASK;
|
|
if (firstFragment)
|
|
lhdr |= MP_LONG_FIRST_FLAG;
|
|
if (lastFragment)
|
|
lhdr |= MP_LONG_LAST_FLAG;
|
|
*mtod(m2, u_int32_t *) = htonl(lhdr);
|
|
}
|
|
|
|
/* Add MP protocol number */
|
|
m2 = ng_ppp_addproto(m, PROT_MP,
|
|
priv->conf.links[linkNum].enableProtoComp);
|
|
if (m2 == NULL) {
|
|
if (!lastFragment)
|
|
m_freem(m);
|
|
NG_FREE_META(meta);
|
|
return (ENOBUFS);
|
|
}
|
|
|
|
/* Copy the meta information, if any */
|
|
if (meta != NULL && !lastFragment) {
|
|
MALLOC(meta2, meta_p,
|
|
meta->used_len, M_NETGRAPH, M_NOWAIT);
|
|
if (meta2 == NULL) {
|
|
m_freem(m2);
|
|
NG_FREE_DATA(m, meta);
|
|
return (ENOMEM);
|
|
}
|
|
meta2->allocated_len = meta->used_len;
|
|
bcopy(meta, meta2, meta->used_len);
|
|
} else
|
|
meta2 = meta;
|
|
|
|
/* Send fragment */
|
|
error = ng_ppp_output(node, linkNum, m2, meta2);
|
|
|
|
/* Abort for error */
|
|
if (error != 0) {
|
|
if (!lastFragment)
|
|
NG_FREE_DATA(m, meta);
|
|
return (error);
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Done */
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Computing the optimal fragmentation
|
|
* -----------------------------------
|
|
*
|
|
* This routine tries to compute the optimal fragmentation pattern based
|
|
* on each link's latency, bandwidth, and calculated additional latency.
|
|
* The latter quantity is the additional latency caused by previously
|
|
* written data that has not been transmitted yet.
|
|
*
|
|
* This algorithm is only useful when not all of the links have the
|
|
* same latency and bandwidth values.
|
|
*
|
|
* The essential idea is to make the last bit of each fragment of the
|
|
* frame arrive at the opposite end at the exact same time. This greedy
|
|
* algorithm is optimal, in that no other scheduling could result in any
|
|
* packet arriving any sooner unless packets are delivered out of order.
|
|
*
|
|
* Suppose link i has bandwidth b_i (in tens of bytes per milisecond) and
|
|
* latency l_i (in miliseconds). Consider the function function f_i(t)
|
|
* which is equal to the number of bytes that will have arrived at
|
|
* the peer after t miliseconds if we start writing continuously at
|
|
* time t = 0. Then f_i(t) = b_i * (t - l_i) = ((b_i * t) - (l_i * b_i).
|
|
* That is, f_i(t) is a line with slope b_i and y-intersect -(l_i * b_i).
|
|
* Note that the y-intersect is always <= zero because latency can't be
|
|
* negative. Note also that really the function is f_i(t) except when
|
|
* f_i(t) is negative, in which case the function is zero. To take
|
|
* care of this, let Q_i(t) = { if (f_i(t) > 0) return 1; else return 0; }.
|
|
* So the actual number of bytes that will have arrived at the peer after
|
|
* t miliseconds is f_i(t) * Q_i(t).
|
|
*
|
|
* At any given time, each link has some additional latency a_i >= 0
|
|
* due to previously written fragment(s) which are still in the queue.
|
|
* This value is easily computed from the time since last transmission,
|
|
* the previous latency value, the number of bytes written, and the
|
|
* link's bandwidth.
|
|
*
|
|
* Assume that l_i includes any a_i already, and that the links are
|
|
* sorted by latency, so that l_i <= l_{i+1}.
|
|
*
|
|
* Let N be the total number of bytes in the current frame we are sending.
|
|
*
|
|
* Suppose we were to start writing bytes at time t = 0 on all links
|
|
* simultaneously, which is the most we can possibly do. Then let
|
|
* F(t) be equal to the total number of bytes received by the peer
|
|
* after t miliseconds. Then F(t) = Sum_i (f_i(t) * Q_i(t)).
|
|
*
|
|
* Our goal is simply this: fragment the frame across the links such
|
|
* that the peer is able to reconstruct the completed frame as soon as
|
|
* possible, i.e., at the least possible value of t. Call this value t_0.
|
|
*
|
|
* Then it follows that F(t_0) = N. Our strategy is first to find the value
|
|
* of t_0, and then deduce how many bytes to write to each link.
|
|
*
|
|
* Rewriting F(t_0):
|
|
*
|
|
* t_0 = ( N + Sum_i ( l_i * b_i * Q_i(t_0) ) ) / Sum_i ( b_i * Q_i(t_0) )
|
|
*
|
|
* Now, we note that Q_i(t) is constant for l_i <= t <= l_{i+1}. t_0 will
|
|
* lie in one of these ranges. To find it, we just need to find the i such
|
|
* that F(l_i) <= N <= F(l_{i+1}). Then we compute all the constant values
|
|
* for Q_i() in this range, plug in the remaining values, solving for t_0.
|
|
*
|
|
* Once t_0 is known, then the number of bytes to send on link i is
|
|
* just f_i(t_0) * Q_i(t_0).
|
|
*
|
|
* In other words, we start allocating bytes to the links one at a time.
|
|
* We keep adding links until the frame is completely sent. Some links
|
|
* may not get any bytes because their latency is too high.
|
|
*
|
|
* Is all this work really worth the trouble? Depends on the situation.
|
|
* The bigger the ratio of computer speed to link speed, and the more
|
|
* important total bundle latency is (e.g., for interactive response time),
|
|
* the more it's worth it. There is however the cost of calling this
|
|
* function for every frame. The running time is O(n^2) where n is the
|
|
* number of links that receive a non-zero number of bytes.
|
|
*
|
|
* Since latency is measured in miliseconds, the "resolution" of this
|
|
* algorithm is one milisecond.
|
|
*
|
|
* To avoid this algorithm altogether, configure all links to have the
|
|
* same latency and bandwidth.
|
|
*/
|
|
static void
|
|
ng_ppp_mp_strategy(node_p node, int len, int *distrib)
|
|
{
|
|
const priv_p priv = node->private;
|
|
int latency[NG_PPP_MAX_LINKS];
|
|
int sortByLatency[NG_PPP_MAX_LINKS];
|
|
int activeLinkNum, linkNum;
|
|
int t0, total, topSum, botSum;
|
|
struct timeval now;
|
|
int i, numFragments;
|
|
|
|
/* If only one link, this gets real easy */
|
|
if (priv->numActiveLinks == 1) {
|
|
distrib[0] = len;
|
|
return;
|
|
}
|
|
|
|
/* Get current time */
|
|
microtime(&now);
|
|
|
|
/* Compute latencies for each link at this point in time */
|
|
for (activeLinkNum = 0;
|
|
activeLinkNum < priv->numActiveLinks; activeLinkNum++) {
|
|
struct timeval diff;
|
|
int xmitBytes;
|
|
|
|
/* Start with base latency value */
|
|
linkNum = priv->activeLinks[activeLinkNum];
|
|
latency[activeLinkNum] = priv->conf.links[linkNum].latency;
|
|
sortByLatency[activeLinkNum] = activeLinkNum; /* see below */
|
|
|
|
/* Any additional latency? */
|
|
if (priv->qstat[activeLinkNum].bytesInQueue == 0)
|
|
continue;
|
|
|
|
/* Compute time delta since last write */
|
|
diff = now;
|
|
timevalsub(&diff, &priv->qstat[activeLinkNum].lastWrite);
|
|
if (now.tv_sec < 0 || diff.tv_sec >= 10) { /* sanity */
|
|
priv->qstat[activeLinkNum].bytesInQueue = 0;
|
|
continue;
|
|
}
|
|
|
|
/* How many bytes could have transmitted since last write? */
|
|
xmitBytes = priv->conf.links[linkNum].bandwidth * diff.tv_sec
|
|
+ (priv->conf.links[linkNum].bandwidth
|
|
* (diff.tv_usec / 1000)) / 100;
|
|
priv->qstat[activeLinkNum].bytesInQueue -= xmitBytes;
|
|
if (priv->qstat[activeLinkNum].bytesInQueue < 0)
|
|
priv->qstat[activeLinkNum].bytesInQueue = 0;
|
|
else
|
|
latency[activeLinkNum] +=
|
|
(100 * priv->qstat[activeLinkNum].bytesInQueue)
|
|
/ priv->conf.links[linkNum].bandwidth;
|
|
}
|
|
|
|
/* Sort links by latency */
|
|
compareLatencies = latency;
|
|
qsort(sortByLatency,
|
|
priv->numActiveLinks, sizeof(*sortByLatency), ng_ppp_intcmp);
|
|
compareLatencies = NULL;
|
|
|
|
/* Find the interval we need (add links in sortByLatency[] order) */
|
|
for (numFragments = 1;
|
|
numFragments < priv->numActiveLinks; numFragments++) {
|
|
for (total = i = 0; i < numFragments; i++) {
|
|
int flowTime;
|
|
|
|
flowTime = latency[sortByLatency[numFragments]]
|
|
- latency[sortByLatency[i]];
|
|
total += ((flowTime * priv->conf.links[
|
|
priv->activeLinks[sortByLatency[i]]].bandwidth)
|
|
+ 99) / 100;
|
|
}
|
|
if (total >= len)
|
|
break;
|
|
}
|
|
|
|
/* Solve for t_0 in that interval */
|
|
for (topSum = botSum = i = 0; i < numFragments; i++) {
|
|
int bw = priv->conf.links[
|
|
priv->activeLinks[sortByLatency[i]]].bandwidth;
|
|
|
|
topSum += latency[sortByLatency[i]] * bw; /* / 100 */
|
|
botSum += bw; /* / 100 */
|
|
}
|
|
t0 = ((len * 100) + topSum + botSum / 2) / botSum;
|
|
|
|
/* Compute f_i(t_0) all i */
|
|
bzero(distrib, priv->numActiveLinks * sizeof(*distrib));
|
|
for (total = i = 0; i < numFragments; i++) {
|
|
int bw = priv->conf.links[
|
|
priv->activeLinks[sortByLatency[i]]].bandwidth;
|
|
|
|
distrib[sortByLatency[i]] =
|
|
(bw * (t0 - latency[sortByLatency[i]]) + 50) / 100;
|
|
total += distrib[sortByLatency[i]];
|
|
}
|
|
|
|
/* Deal with any rounding error */
|
|
if (total < len) {
|
|
int fast = 0;
|
|
|
|
/* Find the fastest link */
|
|
for (i = 1; i < numFragments; i++) {
|
|
if (priv->conf.links[
|
|
priv->activeLinks[sortByLatency[i]]].bandwidth >
|
|
priv->conf.links[
|
|
priv->activeLinks[sortByLatency[fast]]].bandwidth)
|
|
fast = i;
|
|
}
|
|
distrib[sortByLatency[fast]] += len - total;
|
|
} else while (total > len) {
|
|
int delta, slow = 0;
|
|
|
|
/* Find the slowest link that still has bytes to remove */
|
|
for (i = 1; i < numFragments; i++) {
|
|
if (distrib[sortByLatency[slow]] == 0
|
|
|| (distrib[sortByLatency[i]] > 0
|
|
&& priv->conf.links[priv->activeLinks[
|
|
sortByLatency[i]]].bandwidth <
|
|
priv->conf.links[priv->activeLinks[
|
|
sortByLatency[slow]]].bandwidth))
|
|
slow = i;
|
|
}
|
|
delta = total - len;
|
|
if (delta > distrib[sortByLatency[slow]])
|
|
delta = distrib[sortByLatency[slow]];
|
|
distrib[sortByLatency[slow]] -= delta;
|
|
total -= delta;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Compare two integers
|
|
*/
|
|
static int
|
|
ng_ppp_intcmp(const void *v1, const void *v2)
|
|
{
|
|
const int index1 = *((const int *) v1);
|
|
const int index2 = *((const int *) v2);
|
|
|
|
return compareLatencies[index1] - compareLatencies[index2];
|
|
}
|
|
|
|
/*
|
|
* Prepend a possibly compressed PPP protocol number in front of a frame
|
|
*/
|
|
static struct mbuf *
|
|
ng_ppp_addproto(struct mbuf *m, int proto, int compOK)
|
|
{
|
|
int psize = (PROT_COMPRESSABLE(proto) && compOK) ? 1 : 2;
|
|
|
|
/* Add protocol number */
|
|
M_PREPEND(m, psize, M_NOWAIT);
|
|
if (m == NULL || (m->m_len < psize && (m = m_pullup(m, psize)) == NULL))
|
|
return (NULL);
|
|
if (psize == 1)
|
|
*mtod(m, u_char *) = (u_char)proto;
|
|
else
|
|
*mtod(m, u_int16_t *) = htons((u_int16_t)proto);
|
|
return (m);
|
|
}
|
|
|
|
/*
|
|
* Update private information that is derived from other private information
|
|
*/
|
|
static void
|
|
ng_ppp_update(node_p node, int newConf)
|
|
{
|
|
const priv_p priv = node->private;
|
|
int i;
|
|
|
|
/* Update active status for VJ Compression */
|
|
priv->vjCompHooked = priv->hooks[HOOK_INDEX_VJC_IP] != NULL
|
|
&& priv->hooks[HOOK_INDEX_VJC_COMP] != NULL
|
|
&& priv->hooks[HOOK_INDEX_VJC_UNCOMP] != NULL
|
|
&& priv->hooks[HOOK_INDEX_VJC_VJIP] != NULL;
|
|
|
|
/* Increase latency for each link an amount equal to one MP header */
|
|
if (newConf) {
|
|
for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
|
|
int hdrBytes;
|
|
|
|
hdrBytes = (priv->conf.links[i].enableProtoComp ? 1 : 2)
|
|
+ (priv->conf.xmitShortSeq ? 2 : 4);
|
|
priv->conf.links[i].latency +=
|
|
((hdrBytes * priv->conf.links[i].bandwidth) + 50)
|
|
/ 100;
|
|
}
|
|
}
|
|
|
|
/* Update list of active links */
|
|
bzero(&priv->activeLinks, sizeof(priv->activeLinks));
|
|
priv->numActiveLinks = 0;
|
|
priv->allLinksEqual = 1;
|
|
for (i = 0; i < NG_PPP_MAX_LINKS; i++) {
|
|
if (priv->conf.links[i].enableLink && priv->links[i] != NULL) {
|
|
priv->activeLinks[priv->numActiveLinks++] = i;
|
|
if (priv->conf.links[i].latency
|
|
!= priv->conf.links[0].latency
|
|
|| priv->conf.links[i].bandwidth
|
|
!= priv->conf.links[0].bandwidth)
|
|
priv->allLinksEqual = 0;
|
|
}
|
|
}
|
|
|
|
/* Reset MP state if no longer active */
|
|
if (!priv->conf.enableMultilink || priv->numActiveLinks == 0) {
|
|
ng_ppp_free_frags(node);
|
|
priv->mpSeqOut = MP_INITIAL_SEQ;
|
|
bzero(&priv->qstat, sizeof(priv->qstat));
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Determine if a new configuration would represent a valid change
|
|
* from the current configuration and link activity status.
|
|
*/
|
|
static int
|
|
ng_ppp_config_valid(node_p node, const struct ng_ppp_node_config *newConf)
|
|
{
|
|
const priv_p priv = node->private;
|
|
int i, newNumLinksActive;
|
|
|
|
/* Check per-link config and count how many links would be active */
|
|
for (newNumLinksActive = i = 0; i < NG_PPP_MAX_LINKS; i++) {
|
|
if (newConf->links[i].mru < MP_MIN_LINK_MRU)
|
|
return (0);
|
|
if (newConf->links[i].bandwidth == 0)
|
|
return (0);
|
|
if (newConf->links[i].bandwidth > NG_PPP_MAX_BANDWIDTH)
|
|
return (0);
|
|
if (newConf->links[i].latency > NG_PPP_MAX_LATENCY)
|
|
return (0);
|
|
if (newConf->links[i].enableLink && priv->links[i] != NULL)
|
|
newNumLinksActive++;
|
|
}
|
|
|
|
/* Check bundle parameters */
|
|
if (priv->conf.enableMultilink && newConf->mrru < MP_MIN_MRRU)
|
|
return (0);
|
|
|
|
/* At most one link can be active unless multi-link is enabled */
|
|
if (!newConf->enableMultilink && newNumLinksActive > 1)
|
|
return (0);
|
|
|
|
/* Disallow changes to multi-link configuration while MP is active */
|
|
if (priv->numActiveLinks > 0 && newNumLinksActive > 0) {
|
|
if (!priv->conf.enableMultilink != !newConf->enableMultilink
|
|
|| !priv->conf.xmitShortSeq != !newConf->xmitShortSeq
|
|
|| !priv->conf.recvShortSeq != !newConf->recvShortSeq)
|
|
return (0);
|
|
}
|
|
|
|
/* Configuration change is valid */
|
|
return (1);
|
|
}
|
|
|
|
/*
|
|
* Free all entries in the fragment queue
|
|
*/
|
|
static void
|
|
ng_ppp_free_frags(node_p node)
|
|
{
|
|
const priv_p priv = node->private;
|
|
struct ng_ppp_frag *qent, *next;
|
|
|
|
for (qent = CIRCLEQ_FIRST(&priv->frags);
|
|
qent != (void *) &priv->frags; qent = next) {
|
|
next = CIRCLEQ_NEXT(qent, f_qent);
|
|
NG_FREE_DATA(qent->data, qent->meta);
|
|
FREE(qent, M_NETGRAPH);
|
|
}
|
|
CIRCLEQ_INIT(&priv->frags);
|
|
}
|
|
|