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freebsd-nq/sys/netgraph/ng_pppoe.c
Archie Cobbs 7b38c4e4d9 RFC 1661 requires that all LCP packets are sent with no address and 
control field compression. The ng_ppp(4) node correctly follows this
rule. However, PPPoE is an exception: when doing PPPoE *all* frames
are sent with address and control field compression.

Alter this node's behavior so that when an outgoing frame is received,
any leading address and control field bytes are removed. This makes
this node compatible with ng_ppp(4).
2000-08-10 20:05:12 +00:00

1524 lines
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/*
* ng_pppoe.c
*
* Copyright (c) 1996-1999 Whistle Communications, Inc.
* All rights reserved.
*
* Subject to the following obligations and disclaimer of warranty, use and
* redistribution of this software, in source or object code forms, with or
* without modifications are expressly permitted by Whistle Communications;
* provided, however, that:
* 1. Any and all reproductions of the source or object code must include the
* copyright notice above and the following disclaimer of warranties; and
* 2. No rights are granted, in any manner or form, to use Whistle
* Communications, Inc. trademarks, including the mark "WHISTLE
* COMMUNICATIONS" on advertising, endorsements, or otherwise except as
* such appears in the above copyright notice or in the software.
*
* THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
* TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
* REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
* INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
* WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
* REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
* SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
* IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
* RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
* WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
* PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* Author: Julian Elischer <julian@whistle.com>
*
* $FreeBSD$
* $Whistle: ng_pppoe.c,v 1.10 1999/11/01 09:24:52 julian Exp $
*/
#if 0
#define AAA printf("pppoe: %s\n", __FUNCTION__ );
#define BBB printf("-%d-", __LINE__ );
#else
#define AAA
#define BBB
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/errno.h>
#include <net/ethernet.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_pppoe.h>
#define SIGNOFF "session closed"
/*
* This section contains the netgraph method declarations for the
* sample node. These methods define the netgraph 'type'.
*/
static ng_constructor_t ng_pppoe_constructor;
static ng_rcvmsg_t ng_pppoe_rcvmsg;
static ng_shutdown_t ng_pppoe_rmnode;
static ng_newhook_t ng_pppoe_newhook;
static ng_connect_t ng_pppoe_connect;
static ng_rcvdata_t ng_pppoe_rcvdata;
static ng_disconnect_t ng_pppoe_disconnect;
/* Netgraph node type descriptor */
static struct ng_type typestruct = {
NG_VERSION,
NG_PPPOE_NODE_TYPE,
NULL,
ng_pppoe_constructor,
ng_pppoe_rcvmsg,
ng_pppoe_rmnode,
ng_pppoe_newhook,
NULL,
ng_pppoe_connect,
ng_pppoe_rcvdata,
ng_pppoe_rcvdata,
ng_pppoe_disconnect,
NULL
};
NETGRAPH_INIT(pppoe, &typestruct);
/*
* States for the session state machine.
* These have no meaning if there is no hook attached yet.
*/
enum state {
PPPOE_SNONE=0, /* [both] Initial state */
PPPOE_LISTENING, /* [Daemon] Listening for discover initiation pkt */
PPPOE_SINIT, /* [Client] Sent discovery initiation */
PPPOE_PRIMED, /* [Server] Awaiting PADI from daemon */
PPPOE_SOFFER, /* [Server] Sent offer message (got PADI)*/
PPPOE_SREQ, /* [Client] Sent a Request */
PPPOE_NEWCONNECTED, /* [Server] Connection established, No data received */
PPPOE_CONNECTED, /* [Both] Connection established, Data received */
PPPOE_DEAD /* [Both] */
};
#define NUMTAGS 20 /* number of tags we are set up to work with */
/*
* Information we store for each hook on each node for negotiating the
* session. The mbuf and cluster are freed once negotiation has completed.
* The whole negotiation block is then discarded.
*/
struct sess_neg {
struct mbuf *m; /* holds cluster with last sent packet */
union packet *pkt; /* points within the above cluster */
struct callout_handle timeout_handle; /* see timeout(9) */
u_int timeout; /* 0,1,2,4,8,16 etc. seconds */
u_int numtags;
struct pppoe_tag *tags[NUMTAGS];
u_int service_len;
u_int ac_name_len;
struct datatag service;
struct datatag ac_name;
};
typedef struct sess_neg *negp;
/*
* Session information that is needed after connection.
*/
struct session {
hook_p hook;
u_int16_t Session_ID;
struct session *hash_next; /* not yet uesed */
enum state state;
char creator[NG_NODELEN + 1]; /* who to notify */
struct pppoe_full_hdr pkt_hdr; /* used when connected */
negp neg; /* used when negotiating */
};
typedef struct session *sessp;
/*
* Information we store for each node
*/
struct PPPOE {
node_p node; /* back pointer to node */
hook_p ethernet_hook;
hook_p debug_hook;
u_int packets_in; /* packets in from ethernet */
u_int packets_out; /* packets out towards ethernet */
u_int32_t flags;
/*struct session *buckets[HASH_SIZE];*/ /* not yet used */
};
typedef struct PPPOE *priv_p;
const struct ether_header eh_prototype =
{{0xff,0xff,0xff,0xff,0xff,0xff},
{0x00,0x00,0x00,0x00,0x00,0x00},
ETHERTYPE_PPPOE_DISC};
union uniq {
char bytes[sizeof(void *)];
void * pointer;
};
#define LEAVE(x) do { error = x; goto quit; } while(0)
static void pppoe_start(sessp sp);
static void sendpacket(sessp sp);
static void pppoe_ticker(void *arg);
static struct pppoe_tag* scan_tags(sessp sp, struct pppoe_hdr* ph);
static int pppoe_send_event(sessp sp, enum cmd cmdid);
/*************************************************************************
* Some basic utilities from the Linux version with author's permission.*
* Author: Michal Ostrowski <mostrows@styx.uwaterloo.ca> *
************************************************************************/
/*
* Generate a new session id
* XXX find out the FreeBSD locking scheme.
*/
static u_int16_t
get_new_sid(node_p node)
{
static int pppoe_sid = 10;
sessp sp;
hook_p hook;
u_int16_t val;
priv_p privp = node->private;
AAA
restart:
val = pppoe_sid++;
/*
* Spec says 0xFFFF is reserved.
* Also don't use 0x0000
*/
if (val == 0xffff) {
pppoe_sid = 20;
goto restart;
}
/* Check it isn't already in use */
LIST_FOREACH(hook, &node->hooks, hooks) {
/* don't check special hooks */
if ((hook->private == &privp->debug_hook)
|| (hook->private == &privp->ethernet_hook))
continue;
sp = hook->private;
if (sp->Session_ID == val)
goto restart;
}
return val;
}
/*
* Return the location where the next tag can be put
*/
static __inline struct pppoe_tag*
next_tag(struct pppoe_hdr* ph)
{
return (struct pppoe_tag*)(((char*)&ph->tag[0]) + ntohs(ph->length));
}
/*
* Look for a tag of a specific type
* Don't trust any length the other end says.
* but assume we already sanity checked ph->length.
*/
static struct pppoe_tag*
get_tag(struct pppoe_hdr* ph, u_int16_t idx)
{
char *end = (char *)next_tag(ph);
char *ptn;
struct pppoe_tag *pt = &ph->tag[0];
/*
* Keep processing tags while a tag header will still fit.
*/
AAA
while((char*)(pt + 1) <= end) {
/*
* If the tag data would go past the end of the packet, abort.
*/
ptn = (((char *)(pt + 1)) + ntohs(pt->tag_len));
if(ptn > end)
return NULL;
if(pt->tag_type == idx)
return pt;
pt = (struct pppoe_tag*)ptn;
}
return NULL;
}
/**************************************************************************
* inlines to initialise or add tags to a session's tag list,
**************************************************************************/
/*
* Initialise the session's tag list
*/
static void
init_tags(sessp sp)
{
AAA
if(sp->neg == NULL) {
printf("pppoe: asked to init NULL neg pointer\n");
return;
}
sp->neg->numtags = 0;
}
static void
insert_tag(sessp sp, struct pppoe_tag *tp)
{
int i;
negp neg;
AAA
if((neg = sp->neg) == NULL) {
printf("pppoe: asked to use NULL neg pointer\n");
return;
}
if ((i = neg->numtags++) < NUMTAGS) {
neg->tags[i] = tp;
} else {
printf("pppoe: asked to add too many tags to packet\n");
neg->numtags--;
}
}
/*
* Make up a packet, using the tags filled out for the session.
*
* Assume that the actual pppoe header and ethernet header
* are filled out externally to this routine.
* Also assume that neg->wh points to the correct
* location at the front of the buffer space.
*/
static void
make_packet(sessp sp) {
struct pppoe_full_hdr *wh = &sp->neg->pkt->pkt_header;
struct pppoe_tag **tag;
char *dp;
int count;
int tlen;
u_int16_t length = 0;
AAA
if ((sp->neg == NULL) || (sp->neg->m == NULL)) {
printf("pppoe: make_packet called from wrong state\n");
}
dp = (char *)wh->ph.tag;
for (count = 0, tag = sp->neg->tags;
((count < sp->neg->numtags) && (count < NUMTAGS));
tag++, count++) {
tlen = ntohs((*tag)->tag_len) + sizeof(**tag);
if ((length + tlen) > (ETHER_MAX_LEN - 4 - sizeof(*wh))) {
printf("pppoe: tags too long\n");
sp->neg->numtags = count;
break; /* XXX chop off what's too long */
}
bcopy((char *)*tag, (char *)dp, tlen);
length += tlen;
dp += tlen;
}
wh->ph.length = htons(length);
sp->neg->m->m_len = length + sizeof(*wh);
sp->neg->m->m_pkthdr.len = length + sizeof(*wh);
}
/**************************************************************************
* Routine to match a service offered *
**************************************************************************/
/*
* Find a hook that has a service string that matches that
* we are seeking. for now use a simple string.
* In the future we may need something like regexp().
* for testing allow a null string to match 1st found and a null service
* to match all requests. Also make '*' do the same.
*/
static hook_p
pppoe_match_svc(node_p node, char *svc_name, int svc_len)
{
sessp sp = NULL;
negp neg = NULL;
priv_p privp = node->private;
hook_p hook;
AAA
LIST_FOREACH(hook, &node->hooks, hooks) {
/* skip any hook that is debug or ethernet */
if ((hook->private == &privp->debug_hook)
|| (hook->private == &privp->ethernet_hook))
continue;
sp = hook->private;
/* Skip any sessions which are not in LISTEN mode. */
if ( sp->state != PPPOE_LISTENING)
continue;
neg = sp->neg;
/* XXX check validity of this */
/* special case, NULL request. match 1st found. */
if (svc_len == 0)
break;
/* XXX check validity of this */
/* Special case for a blank or "*" service name (wildcard) */
if ((neg->service_len == 0)
|| ((neg->service_len == 1)
&& (neg->service.data[0] == '*'))) {
break;
}
/* If the lengths don't match, that aint it. */
if (neg->service_len != svc_len)
continue;
/* An exact match? */
if (strncmp(svc_name, neg->service.data, svc_len) == 0)
break;
}
return (hook);
}
/**************************************************************************
* Routine to find a particular session that matches an incoming packet *
**************************************************************************/
static hook_p
pppoe_findsession(node_p node, struct pppoe_full_hdr *wh)
{
sessp sp = NULL;
hook_p hook = NULL;
priv_p privp = node->private;
u_int16_t session = ntohs(wh->ph.sid);
/*
* find matching peer/session combination.
*/
AAA
LIST_FOREACH(hook, &node->hooks, hooks) {
/* don't check special hooks */
if ((hook->private == &privp->debug_hook)
|| (hook->private == &privp->ethernet_hook)) {
continue;
}
sp = hook->private;
if ( ( (sp->state == PPPOE_CONNECTED)
|| (sp->state == PPPOE_NEWCONNECTED) )
&& (sp->Session_ID == session)
&& (bcmp(sp->pkt_hdr.eh.ether_dhost,
wh->eh.ether_shost,
ETHER_ADDR_LEN)) == 0) {
break;
}
}
return (hook);
}
static hook_p
pppoe_finduniq(node_p node, struct pppoe_tag *tag)
{
hook_p hook = NULL;
priv_p privp = node->private;
union uniq uniq;
AAA
bcopy(tag->tag_data, uniq.bytes, sizeof(void *));
/* cycle through all known hooks */
LIST_FOREACH(hook, &node->hooks, hooks) {
/* don't check special hooks */
if ((hook->private == &privp->debug_hook)
|| (hook->private == &privp->ethernet_hook))
continue;
if (uniq.pointer == hook->private)
break;
}
return (hook);
}
/**************************************************************************
* start of Netgraph entrypoints *
**************************************************************************/
/*
* Allocate the private data structure and the generic node
* and link them together.
*
* ng_make_node_common() returns with a generic node struct
* with a single reference for us.. we transfer it to the
* private structure.. when we free the private struct we must
* unref the node so it gets freed too.
*
* If this were a device node than this work would be done in the attach()
* routine and the constructor would return EINVAL as you should not be able
* to creatednodes that depend on hardware (unless you can add the hardware :)
*/
static int
ng_pppoe_constructor(node_p *nodep)
{
priv_p privdata;
int error;
AAA
/* Initialize private descriptor */
MALLOC(privdata, priv_p, sizeof(*privdata), M_NETGRAPH, M_WAITOK);
if (privdata == NULL)
return (ENOMEM);
bzero(privdata, sizeof(*privdata));
/* Call the 'generic' (ie, superclass) node constructor */
if ((error = ng_make_node_common(&typestruct, nodep))) {
FREE(privdata, M_NETGRAPH);
return (error);
}
/* Link structs together; this counts as our one reference to *nodep */
(*nodep)->private = privdata;
privdata->node = *nodep;
return (0);
}
/*
* Give our ok for a hook to be added...
* point the hook's private info to the hook structure.
*
* The following hook names are special:
* Ethernet: the hook that should be connected to a NIC.
* debug: copies of data sent out here (when I write the code).
*/
static int
ng_pppoe_newhook(node_p node, hook_p hook, const char *name)
{
const priv_p privp = node->private;
sessp sp;
AAA
if (strcmp(name, NG_PPPOE_HOOK_ETHERNET) == 0) {
privp->ethernet_hook = hook;
hook->private = &privp->ethernet_hook;
} else if (strcmp(name, NG_PPPOE_HOOK_DEBUG) == 0) {
privp->debug_hook = hook;
hook->private = &privp->debug_hook;
} else {
/*
* Any other unique name is OK.
* The infrastructure has already checked that it's unique,
* so just allocate it and hook it in.
*/
MALLOC(sp, sessp, sizeof(*sp), M_NETGRAPH, M_WAITOK);
if (sp == NULL) {
return (ENOMEM);
}
bzero(sp, sizeof(*sp));
hook->private = sp;
sp->hook = hook;
}
return(0);
}
/*
* Get a netgraph control message.
* Check it is one we understand. If needed, send a response.
* We sometimes save the address for an async action later.
* Always free the message.
*/
static int
ng_pppoe_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
struct ng_mesg **rptr, hook_p lasthook)
{
priv_p privp = node->private;
struct ngpppoe_init_data *ourmsg = NULL;
struct ng_mesg *resp = NULL;
int error = 0;
hook_p hook = NULL;
sessp sp = NULL;
negp neg = NULL;
AAA
/* Deal with message according to cookie and command */
switch (msg->header.typecookie) {
case NGM_PPPOE_COOKIE:
switch (msg->header.cmd) {
case NGM_PPPOE_CONNECT:
case NGM_PPPOE_LISTEN:
case NGM_PPPOE_OFFER:
ourmsg = (struct ngpppoe_init_data *)msg->data;
if (( sizeof(*ourmsg) > msg->header.arglen)
|| ((sizeof(*ourmsg) + ourmsg->data_len)
> msg->header.arglen)) {
printf("pppoe_rcvmsg: bad arg size");
LEAVE(EMSGSIZE);
}
if (ourmsg->data_len > PPPOE_SERVICE_NAME_SIZE) {
printf("pppoe: init data too long (%d)\n",
ourmsg->data_len);
LEAVE(EMSGSIZE);
}
/* make sure strcmp will terminate safely */
ourmsg->hook[sizeof(ourmsg->hook) - 1] = '\0';
/* cycle through all known hooks */
LIST_FOREACH(hook, &node->hooks, hooks) {
if (hook->name
&& strcmp(hook->name, ourmsg->hook) == 0)
break;
}
if (hook == NULL) {
LEAVE(ENOENT);
}
if ((hook->private == &privp->debug_hook)
|| (hook->private == &privp->ethernet_hook)) {
LEAVE(EINVAL);
}
sp = hook->private;
if (sp->state |= PPPOE_SNONE) {
printf("pppoe: Session already active\n");
LEAVE(EISCONN);
}
/*
* set up prototype header
*/
MALLOC(neg, negp, sizeof(*neg), M_NETGRAPH, M_WAITOK);
if (neg == NULL) {
printf("pppoe: Session out of memory\n");
LEAVE(ENOMEM);
}
bzero(neg, sizeof(*neg));
MGETHDR(neg->m, M_DONTWAIT, MT_DATA);
if(neg->m == NULL) {
printf("pppoe: Session out of mbufs\n");
FREE(neg, M_NETGRAPH);
LEAVE(ENOBUFS);
}
neg->m->m_pkthdr.rcvif = NULL;
MCLGET(neg->m, M_DONTWAIT);
if ((neg->m->m_flags & M_EXT) == 0) {
printf("pppoe: Session out of mcls\n");
m_freem(neg->m);
FREE(neg, M_NETGRAPH);
LEAVE(ENOBUFS);
}
sp->neg = neg;
callout_handle_init( &neg->timeout_handle);
neg->m->m_len = sizeof(struct pppoe_full_hdr);
neg->pkt = mtod(neg->m, union packet*);
neg->pkt->pkt_header.eh = eh_prototype;
neg->pkt->pkt_header.ph.ver = 0x1;
neg->pkt->pkt_header.ph.type = 0x1;
neg->pkt->pkt_header.ph.sid = 0x0000;
neg->timeout = 0;
strncpy(sp->creator, retaddr, NG_NODELEN);
sp->creator[NG_NODELEN] = '\0';
}
switch (msg->header.cmd) {
case NGM_PPPOE_GET_STATUS:
{
struct ngpppoestat *stats;
NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT);
if (!resp) {
LEAVE(ENOMEM);
}
stats = (struct ngpppoestat *) resp->data;
stats->packets_in = privp->packets_in;
stats->packets_out = privp->packets_out;
break;
}
case NGM_PPPOE_CONNECT:
/*
* Check the hook exists and is Uninitialised.
* Send a PADI request, and start the timeout logic.
* Store the originator of this message so we can send
* a success of fail message to them later.
* Move the session to SINIT
* Set up the session to the correct state and
* start it.
*/
neg->service.hdr.tag_type = PTT_SRV_NAME;
neg->service.hdr.tag_len =
htons((u_int16_t)ourmsg->data_len);
if (ourmsg->data_len) {
bcopy(ourmsg->data,
neg->service.data, ourmsg->data_len);
}
neg->service_len = ourmsg->data_len;
pppoe_start(sp);
break;
case NGM_PPPOE_LISTEN:
/*
* Check the hook exists and is Uninitialised.
* Install the service matching string.
* Store the originator of this message so we can send
* a success of fail message to them later.
* Move the hook to 'LISTENING'
*/
neg->service.hdr.tag_type = PTT_SRV_NAME;
neg->service.hdr.tag_len =
htons((u_int16_t)ourmsg->data_len);
if (ourmsg->data_len) {
bcopy(ourmsg->data,
neg->service.data, ourmsg->data_len);
}
neg->service_len = ourmsg->data_len;
neg->pkt->pkt_header.ph.code = PADT_CODE;
/*
* wait for PADI packet coming from ethernet
*/
sp->state = PPPOE_LISTENING;
break;
case NGM_PPPOE_OFFER:
/*
* Check the hook exists and is Uninitialised.
* Store the originator of this message so we can send
* a success of fail message to them later.
* Store the AC-Name given and go to PRIMED.
*/
neg->ac_name.hdr.tag_type = PTT_AC_NAME;
neg->ac_name.hdr.tag_len =
htons((u_int16_t)ourmsg->data_len);
if (ourmsg->data_len) {
bcopy(ourmsg->data,
neg->ac_name.data, ourmsg->data_len);
}
neg->ac_name_len = ourmsg->data_len;
neg->pkt->pkt_header.ph.code = PADO_CODE;
/*
* Wait for PADI packet coming from hook
*/
sp->state = PPPOE_PRIMED;
break;
default:
LEAVE(EINVAL);
}
break;
default:
LEAVE(EINVAL);
}
/* Take care of synchronous response, if any */
if (rptr)
*rptr = resp;
else if (resp)
FREE(resp, M_NETGRAPH);
/* Free the message and return */
quit:
FREE(msg, M_NETGRAPH);
return(error);
}
/*
* Start a client into the first state. A separate function because
* it can be needed if the negotiation times out.
*/
static void
pppoe_start(sessp sp)
{
struct {
struct pppoe_tag hdr;
union uniq data;
} uniqtag;
/*
* kick the state machine into starting up
*/
AAA
sp->state = PPPOE_SINIT;
/* reset the packet header to broadcast */
sp->neg->pkt->pkt_header.eh = eh_prototype;
sp->neg->pkt->pkt_header.ph.code = PADI_CODE;
uniqtag.hdr.tag_type = PTT_HOST_UNIQ;
uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(uniqtag.data));
uniqtag.data.pointer = sp;
init_tags(sp);
insert_tag(sp, &sp->neg->service.hdr);
insert_tag(sp, &uniqtag.hdr);
make_packet(sp);
sendpacket(sp);
}
/*
* Receive data, and do something with it.
* The caller will never free m or meta, so
* if we use up this data or abort we must free BOTH of these.
*/
static int
ng_pppoe_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
struct mbuf **ret_m, meta_p *ret_meta)
{
node_p node = hook->node;
const priv_p privp = node->private;
sessp sp = hook->private;
struct pppoe_full_hdr *wh;
struct pppoe_hdr *ph;
int error = 0;
u_int16_t session;
u_int16_t length;
u_int8_t code;
struct pppoe_tag *utag = NULL, *tag = NULL;
hook_p sendhook;
struct {
struct pppoe_tag hdr;
union uniq data;
} uniqtag;
negp neg = NULL;
AAA
if (hook->private == &privp->debug_hook) {
/*
* Data from the debug hook gets sent without modification
* straight to the ethernet.
*/
NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
privp->packets_out++;
} else if (hook->private == &privp->ethernet_hook) {
/*
* Incoming data.
* Dig out various fields from the packet.
* use them to decide where to send it.
*/
privp->packets_in++;
if( m->m_len < sizeof(*wh)) {
m = m_pullup(m, sizeof(*wh)); /* Checks length */
if (m == NULL) {
printf("couldn't m_pullup\n");
LEAVE(ENOBUFS);
}
}
wh = mtod(m, struct pppoe_full_hdr *);
ph = &wh->ph;
session = ntohs(wh->ph.sid);
length = ntohs(wh->ph.length);
code = wh->ph.code;
switch(wh->eh.ether_type) {
case ETHERTYPE_PPPOE_DISC:
/*
* We need to try to make sure that the tag area
* is contiguous, or we could wander off the end
* of a buffer and make a mess.
* (Linux wouldn't have this problem).
*/
/*XXX fix this mess */
if (m->m_pkthdr.len <= MHLEN) {
if( m->m_len < m->m_pkthdr.len) {
m = m_pullup(m, m->m_pkthdr.len);
if (m == NULL) {
printf("couldn't m_pullup\n");
LEAVE(ENOBUFS);
}
}
}
if (m->m_len != m->m_pkthdr.len) {
/*
* It's not all in one piece.
* We need to do extra work.
*/
printf("packet fragmented\n");
LEAVE(EMSGSIZE);
}
switch(code) {
case PADI_CODE:
/*
* We are a server:
* Look for a hook with the required service
* and send the ENTIRE packet up there.
* It should come back to a new hook in
* PRIMED state. Look there for further
* processing.
*/
tag = get_tag(ph, PTT_SRV_NAME);
if (tag == NULL) {
printf("no service tag\n");
LEAVE(ENETUNREACH);
}
sendhook = pppoe_match_svc(hook->node,
tag->tag_data, ntohs(tag->tag_len));
if (sendhook) {
NG_SEND_DATA(error, sendhook, m, meta);
} else {
printf("no such service\n");
LEAVE(ENETUNREACH);
}
break;
case PADO_CODE:
/*
* We are a client:
* Use the host_uniq tag to find the
* hook this is in response to.
* Received #2, now send #3
* For now simply accept the first we receive.
*/
utag = get_tag(ph, PTT_HOST_UNIQ);
if ((utag == NULL)
|| (ntohs(utag->tag_len) != sizeof(sp))) {
printf("no host unique field\n");
LEAVE(ENETUNREACH);
}
sendhook = pppoe_finduniq(node, utag);
if (sendhook == NULL) {
printf("no matching session\n");
LEAVE(ENETUNREACH);
}
/*
* Check the session is in the right state.
* It needs to be in PPPOE_SINIT.
*/
sp = sendhook->private;
if (sp->state != PPPOE_SINIT) {
printf("session in wrong state\n");
LEAVE(ENETUNREACH);
}
neg = sp->neg;
untimeout(pppoe_ticker, sendhook,
neg->timeout_handle);
/*
* This is the first time we hear
* from the server, so note it's
* unicast address, replacing the
* broadcast address .
*/
bcopy(wh->eh.ether_shost,
neg->pkt->pkt_header.eh.ether_dhost,
ETHER_ADDR_LEN);
neg->timeout = 0;
neg->pkt->pkt_header.ph.code = PADR_CODE;
init_tags(sp);
insert_tag(sp, &neg->service.hdr); /* Service */
if ((tag = get_tag(ph, PTT_AC_COOKIE)))
insert_tag(sp, tag); /* return cookie */
if ((tag = get_tag(ph, PTT_AC_NAME)))
insert_tag(sp, tag); /* return it */
insert_tag(sp, utag); /* Host Unique */
scan_tags(sp, ph);
make_packet(sp);
sp->state = PPPOE_SREQ;
sendpacket(sp);
break;
case PADR_CODE:
/*
* We are a server:
* Use the ac_cookie tag to find the
* hook this is in response to.
*/
utag = get_tag(ph, PTT_AC_COOKIE);
if ((utag == NULL)
|| (ntohs(utag->tag_len) != sizeof(sp))) {
LEAVE(ENETUNREACH);
}
sendhook = pppoe_finduniq(node, utag);
if (sendhook == NULL) {
LEAVE(ENETUNREACH);
}
/*
* Check the session is in the right state.
* It needs to be in PPPOE_SOFFER
* or PPPOE_NEWCONNECTED. If the latter,
* then this is a retry by the client.
* so be nice, and resend.
*/
sp = sendhook->private;
if (sp->state == PPPOE_NEWCONNECTED) {
/*
* Whoa! drop back to resend that
* PADS packet.
* We should still have a copy of it.
*/
sp->state = PPPOE_SOFFER;
}
if (sp->state != PPPOE_SOFFER) {
LEAVE (ENETUNREACH);
break;
}
neg = sp->neg;
untimeout(pppoe_ticker, sendhook,
neg->timeout_handle);
neg->pkt->pkt_header.ph.code = PADS_CODE;
if (sp->Session_ID == 0)
neg->pkt->pkt_header.ph.sid =
htons(sp->Session_ID
= get_new_sid(node));
neg->timeout = 0;
/*
* start working out the tags to respond with.
*/
init_tags(sp);
insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
if ((tag = get_tag(ph, PTT_SRV_NAME)))
insert_tag(sp, tag);/* return service */
if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
insert_tag(sp, tag); /* return it */
insert_tag(sp, utag); /* ac_cookie */
scan_tags(sp, ph);
make_packet(sp);
sp->state = PPPOE_NEWCONNECTED;
sendpacket(sp);
/*
* Having sent the last Negotiation header,
* Set up the stored packet header to
* be correct for the actual session.
* But keep the negotialtion stuff
* around in case we need to resend this last
* packet. We'll discard it when we move
* from NEWCONNECTED to CONNECTED
*/
sp->pkt_hdr = neg->pkt->pkt_header;
sp->pkt_hdr.eh.ether_type
= ETHERTYPE_PPPOE_SESS;
sp->pkt_hdr.ph.code = 0;
pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
break;
case PADS_CODE:
/*
* We are a client:
* Use the host_uniq tag to find the
* hook this is in response to.
* take the session ID and store it away.
* Also make sure the pre-made header is
* correct and set us into Session mode.
*/
utag = get_tag(ph, PTT_HOST_UNIQ);
if ((utag == NULL)
|| (ntohs(utag->tag_len) != sizeof(sp))) {
LEAVE (ENETUNREACH);
break;
}
sendhook = pppoe_finduniq(node, utag);
if (sendhook == NULL) {
LEAVE(ENETUNREACH);
}
/*
* Check the session is in the right state.
* It needs to be in PPPOE_SREQ.
*/
sp = sendhook->private;
if (sp->state != PPPOE_SREQ) {
LEAVE(ENETUNREACH);
}
neg = sp->neg;
untimeout(pppoe_ticker, sendhook,
neg->timeout_handle);
neg->pkt->pkt_header.ph.sid = wh->ph.sid;
sp->Session_ID = ntohs(wh->ph.sid);
neg->timeout = 0;
sp->state = PPPOE_CONNECTED;
/*
* Now we have gone to Connected mode,
* Free all resources needed for
* negotiation.
* Keep a copy of the header we will be using.
*/
sp->pkt_hdr = neg->pkt->pkt_header;
sp->pkt_hdr.eh.ether_type
= ETHERTYPE_PPPOE_SESS;
sp->pkt_hdr.ph.code = 0;
m_freem(neg->m);
FREE(sp->neg, M_NETGRAPH);
sp->neg = NULL;
pppoe_send_event(sp, NGM_PPPOE_SUCCESS);
break;
case PADT_CODE:
/*
* Send a 'close' message to the controlling
* process (the one that set us up);
* And then tear everything down.
*
* Find matching peer/session combination.
*/
sendhook = pppoe_findsession(node, wh);
NG_FREE_DATA(m, meta); /* no longer needed */
if (sendhook == NULL) {
LEAVE(ENETUNREACH);
}
/* send message to creator */
/* close hook */
if (sendhook) {
ng_destroy_hook(sendhook);
}
break;
default:
LEAVE(EPFNOSUPPORT);
}
break;
case ETHERTYPE_PPPOE_SESS:
/*
* find matching peer/session combination.
*/
sendhook = pppoe_findsession(node, wh);
if (sendhook == NULL) {
LEAVE (ENETUNREACH);
break;
}
sp = sendhook->private;
m_adj(m, sizeof(*wh));
if (m->m_pkthdr.len < length) {
/* Packet too short, dump it */
LEAVE(EMSGSIZE);
}
/* Also need to trim excess at the end */
if (m->m_pkthdr.len > length) {
m_adj(m, -((int)(m->m_pkthdr.len - length)));
}
if ( sp->state != PPPOE_CONNECTED) {
if (sp->state == PPPOE_NEWCONNECTED) {
sp->state = PPPOE_CONNECTED;
/*
* Now we have gone to Connected mode,
* Free all resources needed for
* negotiation. Be paranoid about
* whether there may be a timeout.
*/
m_freem(sp->neg->m);
untimeout(pppoe_ticker, sendhook,
sp->neg->timeout_handle);
FREE(sp->neg, M_NETGRAPH);
sp->neg = NULL;
} else {
LEAVE (ENETUNREACH);
break;
}
}
NG_SEND_DATA( error, sendhook, m, meta);
break;
default:
LEAVE(EPFNOSUPPORT);
}
} else {
/*
* Not ethernet or debug hook..
*
* The packet has come in on a normal hook.
* We need to find out what kind of hook,
* So we can decide how to handle it.
* Check the hook's state.
*/
sp = hook->private;
switch (sp->state) {
case PPPOE_NEWCONNECTED:
case PPPOE_CONNECTED: {
static const u_char addrctrl[] = { 0xff, 0x03 };
struct pppoe_full_hdr *wh;
/*
* Remove PPP address and control fields, if any.
* For example, ng_ppp(4) always sends LCP packets
* with address and control fields as required by
* generic PPP. PPPoE is an exception to the rule.
*/
if (m->m_pkthdr.len >= 2) {
if (m->m_len < 2 && !(m = m_pullup(m, 2)))
LEAVE(ENOBUFS);
if (bcmp(mtod(m, u_char *), addrctrl, 2) == 0)
m_adj(m, 2);
}
/*
* Bang in a pre-made header, and set the length up
* to be correct. Then send it to the ethernet driver.
* But first correct the length.
*/
sp->pkt_hdr.ph.length = htons((short)(m->m_pkthdr.len));
M_PREPEND(m, sizeof(*wh), M_DONTWAIT);
if (m == NULL) {
LEAVE(ENOBUFS);
}
wh = mtod(m, struct pppoe_full_hdr *);
bcopy(&sp->pkt_hdr, wh, sizeof(*wh));
NG_SEND_DATA( error, privp->ethernet_hook, m, meta);
privp->packets_out++;
break;
}
case PPPOE_PRIMED:
/*
* A PADI packet is being returned by the application
* that has set up this hook. This indicates that it
* wants us to offer service.
*/
neg = sp->neg;
if (m->m_len < sizeof(*wh)) {
m = m_pullup(m, sizeof(*wh));
if (m == NULL) {
LEAVE(ENOBUFS);
}
}
wh = mtod(m, struct pppoe_full_hdr *);
ph = &wh->ph;
session = ntohs(wh->ph.sid);
length = ntohs(wh->ph.length);
code = wh->ph.code;
if ( code != PADI_CODE) {
LEAVE(EINVAL);
};
untimeout(pppoe_ticker, hook,
neg->timeout_handle);
/*
* This is the first time we hear
* from the client, so note it's
* unicast address, replacing the
* broadcast address.
*/
bcopy(wh->eh.ether_shost,
neg->pkt->pkt_header.eh.ether_dhost,
ETHER_ADDR_LEN);
sp->state = PPPOE_SOFFER;
neg->timeout = 0;
neg->pkt->pkt_header.ph.code = PADO_CODE;
/*
* start working out the tags to respond with.
*/
uniqtag.hdr.tag_type = PTT_AC_COOKIE;
uniqtag.hdr.tag_len = htons((u_int16_t)sizeof(sp));
uniqtag.data.pointer = sp;
init_tags(sp);
insert_tag(sp, &neg->ac_name.hdr); /* AC_NAME */
if ((tag = get_tag(ph, PTT_SRV_NAME)))
insert_tag(sp, tag); /* return service */
if ((tag = get_tag(ph, PTT_HOST_UNIQ)))
insert_tag(sp, tag); /* returned hostunique */
insert_tag(sp, &uniqtag.hdr);
/* XXX maybe put the tag in the session store */
scan_tags(sp, ph);
make_packet(sp);
sendpacket(sp);
break;
/*
* Packets coming from the hook make no sense
* to sessions in these states. Throw them away.
*/
case PPPOE_SINIT:
case PPPOE_SREQ:
case PPPOE_SOFFER:
case PPPOE_SNONE:
case PPPOE_LISTENING:
case PPPOE_DEAD:
default:
LEAVE(ENETUNREACH);
}
}
quit:
NG_FREE_DATA(m, meta);
return error;
}
/*
* Do local shutdown processing..
* If we are a persistant device, we might refuse to go away, and
* we'd only remove our links and reset ourself.
*/
static int
ng_pppoe_rmnode(node_p node)
{
const priv_p privdata = node->private;
AAA
node->flags |= NG_INVALID;
ng_cutlinks(node);
ng_unname(node);
node->private = NULL;
ng_unref(privdata->node);
FREE(privdata, M_NETGRAPH);
return (0);
}
/*
* This is called once we've already connected a new hook to the other node.
* It gives us a chance to balk at the last minute.
*/
static int
ng_pppoe_connect(hook_p hook)
{
/* be really amiable and just say "YUP that's OK by me! " */
return (0);
}
/*
* Hook disconnection
*
* Clean up all dangling links and information about the session/hook.
* For this type, removal of the last link destroys the node
*/
static int
ng_pppoe_disconnect(hook_p hook)
{
node_p node = hook->node;
priv_p privp = node->private;
sessp sp;
int hooks;
AAA
hooks = node->numhooks; /* this one already not counted */
if (hook->private == &privp->debug_hook) {
privp->debug_hook = NULL;
} else if (hook->private == &privp->ethernet_hook) {
privp->ethernet_hook = NULL;
ng_rmnode(node);
} else {
sp = hook->private;
if (sp->state != PPPOE_SNONE ) {
pppoe_send_event(sp, NGM_PPPOE_CLOSE);
}
/*
* According to the spec, if we are connected,
* we should send a DISC packet if we are shutting down
* a session.
*/
if ((privp->ethernet_hook)
&& ((sp->state == PPPOE_CONNECTED)
|| (sp->state == PPPOE_NEWCONNECTED))) {
struct mbuf *m;
struct pppoe_full_hdr *wh;
struct pppoe_tag *tag;
int msglen = strlen(SIGNOFF);
void *dummy = NULL;
int error = 0;
/* revert the stored header to DISC/PADT mode */
wh = &sp->pkt_hdr;
wh->ph.code = PADT_CODE;
wh->eh.ether_type = ETHERTYPE_PPPOE_DISC;
/* generate a packet of that type */
MGETHDR(m, M_DONTWAIT, MT_DATA);
if(m == NULL)
printf("pppoe: Session out of mbufs\n");
else {
m->m_pkthdr.rcvif = NULL;
m->m_pkthdr.len = m->m_len = sizeof(*wh);
bcopy((caddr_t)wh, mtod(m, caddr_t),
sizeof(*wh));
/*
* Add a General error message and adjust
* sizes
*/
wh = mtod(m, struct pppoe_full_hdr *);
tag = wh->ph.tag;
tag->tag_type = PTT_GEN_ERR;
tag->tag_len = htons((u_int16_t)msglen);
strncpy(tag->tag_data, SIGNOFF, msglen);
m->m_pkthdr.len = (m->m_len += sizeof(*tag) +
msglen);
wh->ph.length = htons(sizeof(*tag) + msglen);
NG_SEND_DATA(error, privp->ethernet_hook, m,
dummy);
}
}
/*
* As long as we have somewhere to store the timeout handle,
* we may have a timeout pending.. get rid of it.
*/
if (sp->neg) {
untimeout(pppoe_ticker, hook, sp->neg->timeout_handle);
if (sp->neg->m)
m_freem(sp->neg->m);
FREE(sp->neg, M_NETGRAPH);
}
FREE(sp, M_NETGRAPH);
hook->private = NULL;
/* work out how many session hooks there are */
/* Node goes away on last session hook removal */
if (privp->ethernet_hook) hooks -= 1;
if (privp->debug_hook) hooks -= 1;
}
if (node->numhooks == 0)
ng_rmnode(node);
return (0);
}
/*
* timeouts come here.
*/
static void
pppoe_ticker(void *arg)
{
int s = splnet();
hook_p hook = arg;
sessp sp = hook->private;
negp neg = sp->neg;
int error = 0;
struct mbuf *m0 = NULL;
priv_p privp = hook->node->private;
meta_p dummy = NULL;
AAA
switch(sp->state) {
/*
* resend the last packet, using an exponential backoff.
* After a period of time, stop growing the backoff,
* and either leave it, or revert to the start.
*/
case PPPOE_SINIT:
case PPPOE_SREQ:
/* timeouts on these produce resends */
m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
neg->timeout_handle = timeout(pppoe_ticker,
hook, neg->timeout * hz);
if ((neg->timeout <<= 1) > PPPOE_TIMEOUT_LIMIT) {
if (sp->state == PPPOE_SREQ) {
/* revert to SINIT mode */
pppoe_start(sp);
} else {
neg->timeout = PPPOE_TIMEOUT_LIMIT;
}
}
break;
case PPPOE_PRIMED:
case PPPOE_SOFFER:
/* a timeout on these says "give up" */
ng_destroy_hook(hook);
break;
default:
/* timeouts have no meaning in other states */
printf("pppoe: unexpected timeout\n");
}
splx(s);
}
static void
sendpacket(sessp sp)
{
int error = 0;
struct mbuf *m0 = NULL;
hook_p hook = sp->hook;
negp neg = sp->neg;
priv_p privp = hook->node->private;
meta_p dummy = NULL;
AAA
switch(sp->state) {
case PPPOE_LISTENING:
case PPPOE_DEAD:
case PPPOE_SNONE:
case PPPOE_CONNECTED:
printf("pppoe: sendpacket: unexpected state\n");
break;
case PPPOE_NEWCONNECTED:
/* send the PADS without a timeout - we're now connected */
m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
break;
case PPPOE_PRIMED:
/* No packet to send, but set up the timeout */
neg->timeout_handle = timeout(pppoe_ticker,
hook, PPPOE_OFFER_TIMEOUT * hz);
break;
case PPPOE_SOFFER:
/*
* send the offer but if they don't respond
* in PPPOE_OFFER_TIMEOUT seconds, forget about it.
*/
m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
neg->timeout_handle = timeout(pppoe_ticker,
hook, PPPOE_OFFER_TIMEOUT * hz);
break;
case PPPOE_SINIT:
case PPPOE_SREQ:
m0 = m_copypacket(sp->neg->m, M_DONTWAIT);
NG_SEND_DATA( error, privp->ethernet_hook, m0, dummy);
neg->timeout_handle = timeout(pppoe_ticker, hook,
(hz * PPPOE_INITIAL_TIMEOUT));
neg->timeout = PPPOE_INITIAL_TIMEOUT * 2;
break;
default:
error = EINVAL;
printf("pppoe: timeout: bad state\n");
}
/* return (error); */
}
/*
* Parse an incoming packet to see if any tags should be copied to the
* output packet. Don't do any tags that have been handled in the main
* state machine.
*/
static struct pppoe_tag*
scan_tags(sessp sp, struct pppoe_hdr* ph)
{
char *end = (char *)next_tag(ph);
char *ptn;
struct pppoe_tag *pt = &ph->tag[0];
/*
* Keep processing tags while a tag header will still fit.
*/
AAA
while((char*)(pt + 1) <= end) {
/*
* If the tag data would go past the end of the packet, abort.
*/
ptn = (((char *)(pt + 1)) + ntohs(pt->tag_len));
if(ptn > end)
return NULL;
switch (pt->tag_type) {
case PTT_RELAY_SID:
insert_tag(sp, pt);
break;
case PTT_EOL:
return NULL;
case PTT_SRV_NAME:
case PTT_AC_NAME:
case PTT_HOST_UNIQ:
case PTT_AC_COOKIE:
case PTT_VENDOR:
case PTT_SRV_ERR:
case PTT_SYS_ERR:
case PTT_GEN_ERR:
break;
}
pt = (struct pppoe_tag*)ptn;
}
return NULL;
}
static int
pppoe_send_event(sessp sp, enum cmd cmdid)
{
int error;
struct ng_mesg *msg;
struct ngpppoe_sts *sts;
AAA
NG_MKMESSAGE(msg, NGM_PPPOE_COOKIE, cmdid,
sizeof(struct ngpppoe_sts), M_NOWAIT);
sts = (struct ngpppoe_sts *)msg->data;
strncpy(sts->hook, sp->hook->name, NG_HOOKLEN + 1);
error = ng_send_msg(sp->hook->node, msg, sp->creator, NULL);
return (error);
}
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