diff options
Diffstat (limited to 'sys')
-rw-r--r-- | sys/modules/netgraph/etf/Makefile | 10 | ||||
-rw-r--r-- | sys/netgraph/ng_etf.c | 496 | ||||
-rw-r--r-- | sys/netgraph/ng_etf.h | 92 |
3 files changed, 598 insertions, 0 deletions
diff --git a/sys/modules/netgraph/etf/Makefile b/sys/modules/netgraph/etf/Makefile new file mode 100644 index 0000000..423aacb --- /dev/null +++ b/sys/modules/netgraph/etf/Makefile @@ -0,0 +1,10 @@ +# $FreeBSD$ +# Ethertype filter + +COPTS+=-g + +KMOD= ng_etf +SRCS= ng_etf.c +NOMAN= + +.include <bsd.kmod.mk> diff --git a/sys/netgraph/ng_etf.c b/sys/netgraph/ng_etf.c new file mode 100644 index 0000000..62ba8aa --- /dev/null +++ b/sys/netgraph/ng_etf.c @@ -0,0 +1,496 @@ +/*- + * ng_etf.c Ethertype filter + * + * Copyright (c) 2001, FreeBSD Incorporated + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice unmodified, this list of conditions, and the following + * disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON 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 ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * Author: Julian Elischer <julian@freebsd.org> + * + * $FreeBSD$ + */ + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/mbuf.h> +#include <sys/malloc.h> +#include <sys/ctype.h> +#include <sys/errno.h> +#include <sys/queue.h> +#include <sys/syslog.h> + +#include <net/ethernet.h> + +#include <netgraph/ng_message.h> +#include <netgraph/ng_parse.h> +#include <netgraph/ng_etf.h> +#include <netgraph/netgraph.h> + +/* If you do complicated mallocs you may want to do this */ +/* and use it for your mallocs */ +#ifdef NG_SEPARATE_MALLOC +MALLOC_DEFINE(M_NETGRAPH_ETF, "netgraph_etf", "netgraph etf node "); +#else +#define M_NETGRAPH_ETF M_NETGRAPH +#endif + +/* + * This section contains the netgraph method declarations for the + * etf node. These methods define the netgraph 'type'. + */ + +static ng_constructor_t ng_etf_constructor; +static ng_rcvmsg_t ng_etf_rcvmsg; +static ng_shutdown_t ng_etf_shutdown; +static ng_newhook_t ng_etf_newhook; +static ng_connect_t ng_etf_connect; +static ng_rcvdata_t ng_etf_rcvdata; /* note these are both ng_rcvdata_t */ +static ng_disconnect_t ng_etf_disconnect; + +/* Parse type for struct ng_etfstat */ +static const struct ng_parse_struct_info + ng_etf_stat_type_info = NG_ETF_STATS_TYPE_INFO; +static const struct ng_parse_type ng_etf_stat_type = { + &ng_parse_struct_type, + &ng_etf_stat_type_info +}; +/* Parse type for struct ng_setfilter */ +static const struct ng_parse_struct_info + ng_etf_filter_type_info = NG_ETF_FILTER_TYPE_INFO; +static const struct ng_parse_type ng_etf_filter_type = { + &ng_parse_struct_type, + &ng_etf_filter_type_info +}; + +/* List of commands and how to convert arguments to/from ASCII */ +static const struct ng_cmdlist ng_etf_cmdlist[] = { + { + NGM_ETF_COOKIE, + NGM_ETF_GET_STATUS, + "getstatus", + NULL, + &ng_etf_stat_type, + }, + { + NGM_ETF_COOKIE, + NGM_ETF_SET_FLAG, + "setflag", + &ng_parse_int32_type, + NULL + }, + { + NGM_ETF_COOKIE, + NGM_ETF_SET_FILTER, + "setfilter", + &ng_etf_filter_type, + NULL + }, + { 0 } +}; + +/* Netgraph node type descriptor */ +static struct ng_type typestruct = { + NG_ABI_VERSION, + NG_ETF_NODE_TYPE, + NULL, + ng_etf_constructor, + ng_etf_rcvmsg, + ng_etf_shutdown, + ng_etf_newhook, + NULL, + ng_etf_connect, + ng_etf_rcvdata, + ng_etf_disconnect, + ng_etf_cmdlist +}; +NETGRAPH_INIT(etf, &typestruct); + +/* Information we store for each hook on each node */ +struct ETF_hookinfo { + hook_p hook; +}; + +struct filter { + LIST_ENTRY(filter) next; + u_int16_t ethertype; /* network order ethertype */ + hook_p match_hook; /* Hook to use on a match */ +}; + +#define HASHSIZE 16 /* Dont change this without changing HASH() */ +#define HASH(et) ((((et)>>12)+((et)>>8)+((et)>>4)+(et)) & 0x0f) +LIST_HEAD(filterhead, filter); + +/* Information we store for each node */ +struct ETF { + struct ETF_hookinfo downstream_hook; + struct ETF_hookinfo nomatch_hook; + node_p node; /* back pointer to node */ + u_int packets_in; /* packets in from downstream */ + u_int packets_out; /* packets out towards downstream */ + u_int32_t flags; + struct filterhead hashtable[HASHSIZE]; +}; +typedef struct ETF *etf_p; + +static struct filter * +ng_etf_findentry(etf_p etfp, u_int16_t ethertype) +{ + struct filterhead *chain = etfp->hashtable + HASH(ethertype); + struct filter *fil; + + + LIST_FOREACH(fil, chain, next) { + if (fil->ethertype == ethertype) { + return (fil); + } + } + return (NULL); +} + + +/* + * Allocate the private data structure. The generic node has already + * been created. Link them together. We arrive with a reference to the node + * i.e. the reference count is incremented for us already. + */ +static int +ng_etf_constructor(node_p node) +{ + etf_p privdata; + int i; + + /* Initialize private descriptor */ + MALLOC(privdata, etf_p, sizeof(*privdata), M_NETGRAPH_ETF, + M_NOWAIT | M_ZERO); + if (privdata == NULL) + return (ENOMEM); + for (i = 0; i < HASHSIZE; i++) { + LIST_INIT((privdata->hashtable + i)); + } + + /* Link structs together; this counts as our one reference to node */ + NG_NODE_SET_PRIVATE(node, privdata); + privdata->node = node; + return (0); +} + +/* + * Give our ok for a hook to be added... + * All names are ok. Two names are special. + */ +static int +ng_etf_newhook(node_p node, hook_p hook, const char *name) +{ + const etf_p etfp = NG_NODE_PRIVATE(node); + struct ETF_hookinfo *hpriv; + + if (strcmp(name, NG_ETF_HOOK_DOWNSTREAM) == 0) { + etfp->downstream_hook.hook = hook; + NG_HOOK_SET_PRIVATE(hook, &etfp->downstream_hook); + etfp->packets_in = 0; + etfp->packets_out = 0; + } else if (strcmp(name, NG_ETF_HOOK_NOMATCH) == 0) { + etfp->nomatch_hook.hook = hook; + NG_HOOK_SET_PRIVATE(hook, &etfp->nomatch_hook); + } else { + /* + * Any other hook name is valid and can + * later be associated with a filter rule. + */ + MALLOC(hpriv, struct ETF_hookinfo *, sizeof(*hpriv), + M_NETGRAPH_ETF, M_NOWAIT | M_ZERO); + if (hpriv == NULL) { + return (ENOMEM); + } + + NG_HOOK_SET_PRIVATE(hook, hpriv); + hpriv->hook = hook; + } + return(0); +} + +/* + * Get a netgraph control message. + * We actually recieve a queue item that has a pointer to the message. + * If we free the item, the message will be freed too, unless we remove + * it from the item using NGI_GET_MSG(); + * The return address is also stored in the item, as an ng_ID_t, + * accessible as NGI_RETADDR(item); + * Check it is one we understand. If needed, send a response. + * We could save the address for an async action later, but don't here. + * Always free the message. + * The response should be in a malloc'd region that the caller can 'free'. + * The NG_MKRESPONSE macro does all this for us. + * A response is not required. + * Theoretically you could respond defferently to old message types if + * the cookie in the header didn't match what we consider to be current + * (so that old userland programs could continue to work). + */ +static int +ng_etf_rcvmsg(node_p node, item_p item, hook_p lasthook) +{ + const etf_p etfp = NG_NODE_PRIVATE(node); + struct ng_mesg *resp = NULL; + int error = 0; + struct ng_mesg *msg; + + NGI_GET_MSG(item, msg); + /* Deal with message according to cookie and command */ + switch (msg->header.typecookie) { + case NGM_ETF_COOKIE: + switch (msg->header.cmd) { + case NGM_ETF_GET_STATUS: + { + struct ng_etfstat *stats; + + NG_MKRESPONSE(resp, msg, sizeof(*stats), M_NOWAIT); + if (!resp) { + error = ENOMEM; + break; + } + stats = (struct ng_etfstat *) resp->data; + stats->packets_in = etfp->packets_in; + stats->packets_out = etfp->packets_out; + break; + } + case NGM_ETF_SET_FLAG: + if (msg->header.arglen != sizeof(u_int32_t)) { + error = EINVAL; + break; + } + etfp->flags = *((u_int32_t *) msg->data); + break; + case NGM_ETF_SET_FILTER: + { + struct ng_etffilter *f; + struct filter *fil; + hook_p hook; + + /* Check message long enough for this command */ + if (msg->header.arglen != sizeof(*f)) { + error = EINVAL; + break; + } + + /* Make sure hook referenced exists */ + f = (struct ng_etffilter *)msg->data; + hook = ng_findhook(node, f->matchhook); + if (hook == NULL) { + error = ENOENT; + break; + } + + /* and is not the downstream hook */ + if (hook == etfp->downstream_hook.hook) { + error = EINVAL; + break; + } + + /* Check we don't already trap this ethertype */ + if (ng_etf_findentry(etfp, + htons(f->ethertype))) { + error = EEXIST; + break; + } + + /* + * Ok, make the filter and put it in the + * hashtable ready for matching. + */ + MALLOC(fil, struct filter *, sizeof(*fil), + M_NETGRAPH_ETF, M_NOWAIT | M_ZERO); + if (fil == NULL) { + return (ENOMEM); + } + + fil->match_hook = hook; + fil->ethertype = htons(f->ethertype); + LIST_INSERT_HEAD( etfp->hashtable + + HASH(fil->ethertype), + fil, next); + } + break; + default: + error = EINVAL; /* unknown command */ + break; + } + break; + default: + error = EINVAL; /* unknown cookie type */ + break; + } + + /* Take care of synchronous response, if any */ + NG_RESPOND_MSG(error, node, item, resp); + /* Free the message and return */ + NG_FREE_MSG(msg); + return(error); +} + +/* + * Receive data, and do something with it. + * Actually we receive a queue item which holds the data. + * If we free the item it wil also froo the data and metadata unless + * we have previously disassociated them using the NGI_GET_etf() macros. + * Possibly send it out on another link after processing. + * Possibly do something different if it comes from different + * hooks. the caller will never free m or meta, so + * if we use up this data or abort we must free BOTH of these. + * + * If we want, we may decide to force this data to be queued and reprocessed + * at the netgraph NETISR time. + * We would do that by setting the HK_QUEUE flag on our hook. We would do that + * in the connect() method. + */ +static int +ng_etf_rcvdata(hook_p hook, item_p item ) +{ + const etf_p etfp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); + struct ether_header *eh; + int error = 0; + struct mbuf *m; + u_int16_t ethertype; + struct filter *fil; + + if (NG_HOOK_PRIVATE(hook) == NULL) { /* Shouldn't happen but.. */ + NG_FREE_ITEM(item); + } + + /* + * Everything not from the downstream hook goes to the + * downstream hook. But only if it matches the ethertype + * of the source hook. Un matching must go to/from 'nomatch'. + */ + + /* Make sure we have an entire header */ + NGI_GET_M(item, m); + if (m->m_len < sizeof(*eh) ) { + m = m_pullup(m, sizeof(*eh)); + if (m == NULL) { + NG_FREE_ITEM(item); + return(EINVAL); + } + } + + eh = mtod(m, struct ether_header *); + ethertype = eh->ether_type; + fil = ng_etf_findentry(etfp, ethertype); + + /* + * if from downstream, select between a match hook or + * the nomatch hook + */ + if (hook == etfp->downstream_hook.hook) { + etfp->packets_in++; + if (fil && fil->match_hook) { + NG_FWD_NEW_DATA(error, item, fil->match_hook, m); + } else { + NG_FWD_NEW_DATA(error, item,etfp->nomatch_hook.hook, m); + } + } else { + /* + * It must be heading towards the downstream. + * Check that it's ethertype matches + * the filters for it's input hook. + * If it doesn't have one, check it's from nomatch. + */ + if ((fil && (fil->match_hook != hook)) + || ((fil == NULL) && (hook != etfp->nomatch_hook.hook))) { + NG_FREE_ITEM(item); + NG_FREE_M(m); + return (EPROTOTYPE); + } + NG_FWD_NEW_DATA( error, item, etfp->downstream_hook.hook, m); + if (error == 0) { + etfp->packets_out++; + } + } + return (error); +} + +/* + * Do local shutdown processing.. + * All our links and the name have already been removed. + */ +static int +ng_etf_shutdown(node_p node) +{ + const etf_p privdata = NG_NODE_PRIVATE(node); + + NG_NODE_SET_PRIVATE(node, NULL); + NG_NODE_UNREF(privdata->node); + FREE(privdata, M_NETGRAPH_ETF); + 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_etf_connect(hook_p hook) +{ + return (0); +} + +/* + * Hook disconnection + * + * For this type, removal of the last link destroys the node + */ +static int +ng_etf_disconnect(hook_p hook) +{ + const etf_p etfp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); + int i; + struct filter *fil; + + /* purge any rules that refer to this filter */ + for (i = 0; i < HASHSIZE; i++) { + LIST_FOREACH(fil, (etfp->hashtable + i), next) { + if (fil->match_hook == hook) { + LIST_REMOVE(fil, next); + } + } + } + + /* If it's not one of the special hooks, then free it */ + if (hook == etfp->downstream_hook.hook) { + etfp->downstream_hook.hook = NULL; + } else if (hook == etfp->nomatch_hook.hook) { + etfp->nomatch_hook.hook = NULL; + } else { + if (NG_HOOK_PRIVATE(hook)) /* Paranoia */ + FREE(NG_HOOK_PRIVATE(hook), M_NETGRAPH_ETF); + } + + NG_HOOK_SET_PRIVATE(hook, NULL); + + if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) + && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) /* already shutting down? */ + ng_rmnode_self(NG_HOOK_NODE(hook)); + return (0); +} + diff --git a/sys/netgraph/ng_etf.h b/sys/netgraph/ng_etf.h new file mode 100644 index 0000000..58da641 --- /dev/null +++ b/sys/netgraph/ng_etf.h @@ -0,0 +1,92 @@ +/*- + * ng_etf.h + * + * Copyright (c) 2001, FreeBSD Incorporated + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice unmodified, this list of conditions, and the following + * disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON 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 ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * Author: Julian Elischer <julian@freebsd.org> + * + * $FreeBSD$ + */ + +#ifndef _NETGRAPH_ETHERTYPE_FILTER_H_ +#define _NETGRAPH_ETHERTYPE_FILTER_H_ + +/* Node type name. This should be unique among all netgraph node types */ +#define NG_ETF_NODE_TYPE "etf" + +/* Node type cookie. Should also be unique. This value MUST change whenever + an incompatible change is made to this header file, to insure consistency. + The de facto method for generating cookies is to take the output of the + date command: date -u +'%s' */ +#define NGM_ETF_COOKIE 983084516 + +/* Hook names */ +#define NG_ETF_HOOK_DOWNSTREAM "downstream" +#define NG_ETF_HOOK_NOMATCH "nomatch" + +/* Netgraph commands understood by this node type */ +enum { + NGM_ETF_SET_FLAG = 1, + NGM_ETF_GET_STATUS, + NGM_ETF_SET_FILTER, + +}; + +/* This structure is returned by the NGM_ETF_GET_STATUS command */ +struct ng_etfstat { + u_int32_t packets_in; /* packets in from downstream */ + u_int32_t packets_out; /* packets out towards downstream */ +}; + +/* + * This needs to be kept in sync with the above structure definition + */ +#define NG_ETF_STATS_TYPE_INFO { \ + { \ + { "packets_in", &ng_parse_uint32_type }, \ + { "packets_out", &ng_parse_uint32_type }, \ + { NULL }, \ + } \ +} + +/* This structure is returned by the NGM_ETF_GET_STATUS command */ +struct ng_etffilter { + char matchhook[NG_HOOKLEN + 1]; /* hook name */ + u_int16_t ethertype; /* this ethertype to this hook */ +}; + +/* + * This needs to be kept in sync with the above structure definition + */ +#define NG_ETF_FILTER_TYPE_INFO { \ + { \ + { "matchhook", &ng_parse_hookbuf_type }, \ + { "ethertype", &ng_parse_uint16_type }, \ + { NULL }, \ + } \ +} + +#endif /* _NETGRAPH_ETHERTYPE_FILTER_H_ */ |