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