/* * 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 * * $FreeBSD$ * $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 #include #include #include #include #include #include #include #include #include #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 * ************************************************************************/ /* * 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); }