diff options
Diffstat (limited to 'sys/netgraph/ng_tee.c')
-rw-r--r-- | sys/netgraph/ng_tee.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/sys/netgraph/ng_tee.c b/sys/netgraph/ng_tee.c new file mode 100644 index 0000000..476913c --- /dev/null +++ b/sys/netgraph/ng_tee.c @@ -0,0 +1,268 @@ + +/* + * ng_tee.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_tee.c,v 1.16 1999/01/28 23:54:54 julian Exp $ + */ + +/* + * This node is like the tee(1) command and is useful for ``snooping.'' + * It has 4 hooks: left, right, left2right, and right2left. Data + * entering from the right is passed to the left and duplicated on + * right2left, and data entering from the left is passed to the right + * and duplicated on left2right. Data entering from left2right is + * sent to right, and data from right2left to left. + */ + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/errno.h> +#include <sys/kernel.h> +#include <sys/malloc.h> +#include <sys/mbuf.h> +#include <netgraph/ng_message.h> +#include <netgraph/netgraph.h> +#include <netgraph/ng_tee.h> + +/* Per hook info */ +struct hookinfo { + hook_p hook; + int bytes; + int packets; + int flags; +}; + +/* Per node info */ +struct privdata { + node_p node; + int flags; + struct hookinfo left; + struct hookinfo right; + struct hookinfo left2right; + struct hookinfo right2left; +}; +typedef struct privdata *sc_p; + +/* Netgraph methods */ +static int ngt_constructor(node_p *node); +static int ngt_rcvmsg(node_p node, struct ng_mesg *msg, + const char *retaddr, struct ng_mesg **resp); +static int ngt_rmnode(node_p node); +static int ngt_newhook(node_p node, hook_p hook, const char *name); +static int ngt_rcvdata(hook_p hook, struct mbuf *m, meta_p meta); +static int ngt_disconnect(hook_p hook); + +/* Netgraph type descriptor */ +static struct ng_type typestruct = { + NG_VERSION, + NG_TEE_NODE_TYPE, + NULL, + ngt_constructor, + ngt_rcvmsg, + ngt_rmnode, + ngt_newhook, + NULL, + NULL, + ngt_rcvdata, + ngt_rcvdata, + ngt_disconnect +}; +NETGRAPH_INIT(tee, &typestruct); + +/* + * Node constructor + */ +static int +ngt_constructor(node_p *nodep) +{ + sc_p privdata; + int error = 0; + + MALLOC(privdata, sc_p, sizeof(*privdata), M_NETGRAPH, M_WAITOK); + if (privdata == NULL) + return (ENOMEM); + bzero(privdata, sizeof(*privdata)); + + if ((error = ng_make_node_common(&typestruct, nodep))) { + FREE(privdata, M_NETGRAPH); + return (error); + } + (*nodep)->private = privdata; + privdata->node = *nodep; + return (0); +} + +/* + * Add a hook + */ +static int +ngt_newhook(node_p node, hook_p hook, const char *name) +{ + const sc_p sc = node->private; + + if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) { + sc->right.hook = hook; + sc->right.bytes = 0; + sc->right.packets = 0; + hook->private = &sc->right; + } else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) { + sc->left.hook = hook; + sc->left.bytes = 0; + sc->left.packets = 0; + hook->private = &sc->left; + } else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) { + sc->right2left.hook = hook; + sc->right2left.bytes = 0; + sc->right2left.packets = 0; + hook->private = &sc->right2left; + } else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) { + sc->left2right.hook = hook; + sc->left2right.bytes = 0; + sc->left2right.packets = 0; + hook->private = &sc->left2right; + } else + return (EINVAL); + return (0); +} + +/* + * We don't support any type-specific messages + */ +static int +ngt_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr, + struct ng_mesg **resp) +{ + FREE(msg, M_NETGRAPH); + return (EINVAL); +} + +/* + * Receive data on a hook + * + * If data comes in the right link send a copy out right2left, and then + * send the original onwards out through the left link. + * Do the opposite for data coming in from the left link. + * Data coming in right2left or left2right is forwarded + * on through the appropriate destination hook as if it had come + * from the other side. + */ +static int +ngt_rcvdata(hook_p hook, struct mbuf *m, meta_p meta) +{ + const sc_p sc = hook->node->private; + struct hookinfo *hi; + struct hookinfo *dest; + struct hookinfo *dup; + struct mbuf *mdup; + int error = 0; + + if ((hi = hook->private) != NULL) { + if (hi == &sc->left) { + dup = &sc->left2right; + dest = &sc->right; + } else if (hi == &sc->right) { + dup = &sc->right2left; + dest = &sc->left; + } else if (hi == &sc->right2left) { + dup = NULL; + dest = &sc->left; + } else if (hi == &sc->left2right) { + dup = NULL; + dest = &sc->right; + } else + goto out; + if (dup) { + mdup = m_copypacket(m, M_NOWAIT); + if (mdup) { + /* XXX should we duplicate meta? */ + /* for now no. */ + void *x = NULL; + + NG_SEND_DATA(error, dup->hook, mdup, x); + } + } + NG_SEND_DATA(error, dest->hook, m, meta); + } + +out: + NG_FREE_DATA(m, meta); + return (error); +} + +/* + * Shutdown processing + * + * This is tricky. If we have both a left and right hook, then we + * probably want to extricate ourselves and leave the two peers + * still linked to each other. Otherwise we should just shut down as + * a normal node would. + * + * To keep the scope of info correct the routine to "extract" a node + * from two links is in ng_base.c. + */ +static int +ngt_rmnode(node_p node) +{ + const sc_p privdata = node->private; + + node->flags |= NG_INVALID; + if (privdata->left.hook && privdata->right.hook) + ng_bypass(privdata->left.hook, privdata->right.hook); + ng_cutlinks(node); + ng_unname(node); + node->private = NULL; + ng_unref(privdata->node); + FREE(privdata, M_NETGRAPH); + return (0); +} + +/* + * Hook disconnection + */ +static int +ngt_disconnect(hook_p hook) +{ + struct hookinfo *hi; + + if ((hi = hook->private) != NULL) + hi->hook = NULL; + if (hook->node->numhooks == 0) + ng_rmnode(hook->node); + return (0); +} + |