1 2 /* 3 * ng_UI.c 4 * 5 * Copyright (c) 1996-1999 Whistle Communications, Inc. 6 * All rights reserved. 7 * 8 * Subject to the following obligations and disclaimer of warranty, use and 9 * redistribution of this software, in source or object code forms, with or 10 * without modifications are expressly permitted by Whistle Communications; 11 * provided, however, that: 12 * 1. Any and all reproductions of the source or object code must include the 13 * copyright notice above and the following disclaimer of warranties; and 14 * 2. No rights are granted, in any manner or form, to use Whistle 15 * Communications, Inc. trademarks, including the mark "WHISTLE 16 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 17 * such appears in the above copyright notice or in the software. 18 * 19 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 20 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 21 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 22 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 24 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 25 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 26 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 27 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 28 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 29 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 30 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 31 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 34 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 35 * OF SUCH DAMAGE. 36 * 37 * Author: Julian Elischer <julian@whistle.com> 38 * 39 * $FreeBSD$ 40 * $Whistle: ng_UI.c,v 1.14 1999/11/01 09:24:51 julian Exp $ 41 */ 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/errno.h> 46 #include <sys/kernel.h> 47 #include <sys/malloc.h> 48 #include <sys/mbuf.h> 49 #include <sys/conf.h> 50 #include <sys/errno.h> 51 #include <sys/socket.h> 52 #include <sys/syslog.h> 53 54 #include <net/if.h> 55 #include <netinet/in.h> 56 #include <netinet/if_ether.h> 57 58 #include <netgraph/ng_message.h> 59 #include <netgraph/netgraph.h> 60 #include <netgraph/ng_UI.h> 61 62 /* 63 * DEFINITIONS 64 */ 65 66 /* Everything, starting with sdlc on has defined UI as 0x03 */ 67 #define HDLC_UI 0x03 68 69 /* Node private data */ 70 struct private { 71 hook_p downlink; 72 hook_p uplink; 73 }; 74 typedef struct private *priv_p; 75 76 /* Netgraph node methods */ 77 static ng_constructor_t ng_UI_constructor; 78 static ng_rcvmsg_t ng_UI_rcvmsg; 79 static ng_shutdown_t ng_UI_rmnode; 80 static ng_newhook_t ng_UI_newhook; 81 static ng_rcvdata_t ng_UI_rcvdata; 82 static ng_disconnect_t ng_UI_disconnect; 83 84 /* Node type descriptor */ 85 static struct ng_type typestruct = { 86 NG_VERSION, 87 NG_UI_NODE_TYPE, 88 NULL, 89 ng_UI_constructor, 90 ng_UI_rcvmsg, 91 ng_UI_rmnode, 92 ng_UI_newhook, 93 NULL, 94 NULL, 95 ng_UI_rcvdata, 96 ng_UI_rcvdata, 97 ng_UI_disconnect 98 }; 99 NETGRAPH_INIT(UI, &typestruct); 100 101 /************************************************************************ 102 NETGRAPH NODE STUFF 103 ************************************************************************/ 104 105 /* 106 * Create a newborn node. We start with an implicit reference. 107 */ 108 109 static int 110 ng_UI_constructor(node_p *nodep) 111 { 112 priv_p priv; 113 int error; 114 115 /* Allocate private structure */ 116 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_WAITOK); 117 if (priv == NULL) 118 return (ENOMEM); 119 bzero(priv, sizeof(*priv)); 120 121 /* Call generic node constructor */ 122 if ((error = ng_make_node_common(&typestruct, nodep))) { 123 FREE(priv, M_NETGRAPH); 124 return (error); 125 } 126 (*nodep)->private = priv; 127 128 /* Done */ 129 return (0); 130 } 131 132 /* 133 * Give our ok for a hook to be added 134 */ 135 static int 136 ng_UI_newhook(node_p node, hook_p hook, const char *name) 137 { 138 const priv_p priv = node->private; 139 140 if (!strcmp(name, NG_UI_HOOK_DOWNSTREAM)) { 141 if (priv->downlink) 142 return (EISCONN); 143 priv->downlink = hook; 144 } else if (!strcmp(name, NG_UI_HOOK_UPSTREAM)) { 145 if (priv->uplink) 146 return (EISCONN); 147 priv->uplink = hook; 148 } else 149 return (EINVAL); 150 return (0); 151 } 152 153 /* 154 * Receive a control message 155 */ 156 static int 157 ng_UI_rcvmsg(node_p node, struct ng_mesg *msg, 158 const char *raddr, struct ng_mesg **rp) 159 { 160 FREE(msg, M_NETGRAPH); 161 return (EINVAL); 162 } 163 164 #define MAX_ENCAPS_HDR 1 165 #define ERROUT(x) do { error = (x); goto done; } while (0) 166 167 /* 168 * Receive a data frame 169 */ 170 static int 171 ng_UI_rcvdata(hook_p hook, struct mbuf *m, meta_p meta) 172 { 173 const node_p node = hook->node; 174 const priv_p priv = node->private; 175 int error = 0; 176 177 if (hook == priv->downlink) { 178 u_char *start, *ptr; 179 180 if (!m || (m->m_len < MAX_ENCAPS_HDR 181 && !(m = m_pullup(m, MAX_ENCAPS_HDR)))) 182 ERROUT(ENOBUFS); 183 ptr = start = mtod(m, u_char *); 184 185 /* Must be UI frame */ 186 if (*ptr++ != HDLC_UI) 187 ERROUT(0); 188 189 m_adj(m, ptr - start); 190 NG_SEND_DATA(error, priv->uplink, m, meta); /* m -> NULL */ 191 } else if (hook == priv->uplink) { 192 M_PREPEND(m, 1, M_DONTWAIT); /* Prepend IP NLPID */ 193 if (!m) 194 ERROUT(ENOBUFS); 195 mtod(m, u_char *)[0] = HDLC_UI; 196 NG_SEND_DATA(error, priv->downlink, m, meta); /* m -> NULL */ 197 } else 198 panic(__FUNCTION__); 199 200 done: 201 NG_FREE_DATA(m, meta); /* does nothing if m == NULL */ 202 return (error); 203 } 204 205 /* 206 * Shutdown node 207 */ 208 static int 209 ng_UI_rmnode(node_p node) 210 { 211 const priv_p priv = node->private; 212 213 /* Take down netgraph node */ 214 node->flags |= NG_INVALID; 215 ng_cutlinks(node); 216 ng_unname(node); 217 bzero(priv, sizeof(*priv)); 218 FREE(priv, M_NETGRAPH); 219 node->private = NULL; 220 ng_unref(node); 221 return (0); 222 } 223 224 /* 225 * Hook disconnection 226 */ 227 static int 228 ng_UI_disconnect(hook_p hook) 229 { 230 const priv_p priv = hook->node->private; 231 232 if (hook->node->numhooks == 0) 233 ng_rmnode(hook->node); 234 else if (hook == priv->downlink) 235 priv->downlink = NULL; 236 else if (hook == priv->uplink) 237 priv->uplink = NULL; 238 else 239 panic(__FUNCTION__); 240 return (0); 241 } 242 243