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freebsd-dev/sys/netgraph/ng_pppoe.c
julian c823368bff Two simple changes to the kernel internal API for netgraph modules, 
to support future work in flow-control and 'packet reject/replace'
processing modes.

reviewed by: phk, archie
2000-04-28 17:09:00 +00:00

1510 lines
39 KiB
C
Raw Blame History

/*
* 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: {
struct pppoe_full_hdr *wh;
/*
* 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 teh 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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