6 * Copyright (c) 1996-1999 Whistle Communications, Inc.
9 * Subject to the following obligations and disclaimer of warranty, use and
10 * redistribution of this software, in source or object code forms, with or
11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
13 * 1. Any and all reproductions of the source or object code must include the
14 * copyright notice above and the following disclaimer of warranties; and
15 * 2. No rights are granted, in any manner or form, to use Whistle
16 * Communications, Inc. trademarks, including the mark "WHISTLE
17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18 * such appears in the above copyright notice or in the software.
20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
38 * Author: Archie Cobbs <archie@freebsd.org>
41 * $Whistle: ng_async.c,v 1.17 1999/11/01 09:24:51 julian Exp $
45 * This node type implements a PPP style sync <-> async converter.
46 * See RFC 1661 for details of how asynchronous encoding works.
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/kernel.h>
53 #include <sys/malloc.h>
54 #include <sys/errno.h>
56 #include <netgraph/ng_message.h>
57 #include <netgraph/netgraph.h>
58 #include <netgraph/ng_async.h>
59 #include <netgraph/ng_parse.h>
61 #include <net/ppp_defs.h>
63 #ifdef NG_SEPARATE_MALLOC
64 MALLOC_DEFINE(M_NETGRAPH_ASYNC, "netgraph_async", "netgraph async node ");
66 #define M_NETGRAPH_ASYNC M_NETGRAPH
70 /* Async decode state */
75 /* Private data structure */
76 struct ng_async_private {
77 node_p node; /* Our node */
78 hook_p async; /* Asynchronous side */
79 hook_p sync; /* Synchronous side */
80 u_char amode; /* Async hunt/esape mode */
81 u_int16_t fcs; /* Decoded async FCS (so far) */
82 u_char *abuf; /* Buffer to encode sync into */
83 u_char *sbuf; /* Buffer to decode async into */
84 u_int slen; /* Length of data in sbuf */
85 long lasttime; /* Time of last async packet sent */
86 struct ng_async_cfg cfg; /* Configuration */
87 struct ng_async_stat stats; /* Statistics */
89 typedef struct ng_async_private *sc_p;
92 #define ASYNC_BUF_SIZE(smru) (2 * (smru) + 10)
93 #define SYNC_BUF_SIZE(amru) ((amru) + 10)
94 #define ERROUT(x) do { error = (x); goto done; } while (0)
96 /* Netgraph methods */
97 static ng_constructor_t nga_constructor;
98 static ng_rcvdata_t nga_rcvdata;
99 static ng_rcvmsg_t nga_rcvmsg;
100 static ng_shutdown_t nga_shutdown;
101 static ng_newhook_t nga_newhook;
102 static ng_disconnect_t nga_disconnect;
105 static int nga_rcv_sync(const sc_p sc, item_p item);
106 static int nga_rcv_async(const sc_p sc, item_p item);
108 /* Parse type for struct ng_async_cfg */
109 static const struct ng_parse_struct_field nga_config_type_fields[]
110 = NG_ASYNC_CONFIG_TYPE_INFO;
111 static const struct ng_parse_type nga_config_type = {
112 &ng_parse_struct_type,
113 &nga_config_type_fields
116 /* Parse type for struct ng_async_stat */
117 static const struct ng_parse_struct_field nga_stats_type_fields[]
118 = NG_ASYNC_STATS_TYPE_INFO;
119 static const struct ng_parse_type nga_stats_type = {
120 &ng_parse_struct_type,
121 &nga_stats_type_fields
124 /* List of commands and how to convert arguments to/from ASCII */
125 static const struct ng_cmdlist nga_cmdlist[] = {
128 NGM_ASYNC_CMD_SET_CONFIG,
135 NGM_ASYNC_CMD_GET_CONFIG,
142 NGM_ASYNC_CMD_GET_STATS,
149 NGM_ASYNC_CMD_CLR_STATS,
157 /* Define the netgraph node type */
158 static struct ng_type typestruct = {
159 .version = NG_ABI_VERSION,
160 .name = NG_ASYNC_NODE_TYPE,
161 .constructor = nga_constructor,
162 .rcvmsg = nga_rcvmsg,
163 .shutdown = nga_shutdown,
164 .newhook = nga_newhook,
165 .rcvdata = nga_rcvdata,
166 .disconnect = nga_disconnect,
167 .cmdlist = nga_cmdlist
169 NETGRAPH_INIT(async, &typestruct);
172 static const u_int16_t fcstab[];
174 /******************************************************************
175 NETGRAPH NODE METHODS
176 ******************************************************************/
179 * Initialize a new node
182 nga_constructor(node_p node)
186 sc = malloc(sizeof(*sc), M_NETGRAPH_ASYNC, M_NOWAIT | M_ZERO);
189 sc->amode = MODE_HUNT;
191 sc->cfg.amru = NG_ASYNC_DEFAULT_MRU;
192 sc->cfg.smru = NG_ASYNC_DEFAULT_MRU;
193 sc->abuf = malloc(ASYNC_BUF_SIZE(sc->cfg.smru),
194 M_NETGRAPH_ASYNC, M_NOWAIT);
195 if (sc->abuf == NULL)
197 sc->sbuf = malloc(SYNC_BUF_SIZE(sc->cfg.amru),
198 M_NETGRAPH_ASYNC, M_NOWAIT);
199 if (sc->sbuf == NULL) {
200 free(sc->abuf, M_NETGRAPH_ASYNC);
202 free(sc, M_NETGRAPH_ASYNC);
205 NG_NODE_SET_PRIVATE(node, sc);
211 * Reserve a hook for a pending connection
214 nga_newhook(node_p node, hook_p hook, const char *name)
216 const sc_p sc = NG_NODE_PRIVATE(node);
219 if (!strcmp(name, NG_ASYNC_HOOK_ASYNC)) {
221 * We use a static buffer here so only one packet
222 * at a time can be allowed to travel in this direction.
223 * Force Writer semantics.
225 NG_HOOK_FORCE_WRITER(hook);
227 } else if (!strcmp(name, NG_ASYNC_HOOK_SYNC)) {
229 * We use a static state here so only one packet
230 * at a time can be allowed to travel in this direction.
231 * Force Writer semantics.
232 * Since we set this for both directions
233 * we might as well set it for the whole node
234 * bit I haven;t done that (yet).
236 NG_HOOK_FORCE_WRITER(hook);
241 if (*hookp) /* actually can't happen I think [JRE] */
248 * Receive incoming data
251 nga_rcvdata(hook_p hook, item_p item)
253 const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
255 if (hook == sc->sync)
256 return (nga_rcv_sync(sc, item));
257 if (hook == sc->async)
258 return (nga_rcv_async(sc, item));
263 * Receive incoming control message
266 nga_rcvmsg(node_p node, item_p item, hook_p lasthook)
268 const sc_p sc = NG_NODE_PRIVATE(node);
269 struct ng_mesg *resp = NULL;
273 NGI_GET_MSG(item, msg);
274 switch (msg->header.typecookie) {
275 case NGM_ASYNC_COOKIE:
276 switch (msg->header.cmd) {
277 case NGM_ASYNC_CMD_GET_STATS:
278 NG_MKRESPONSE(resp, msg, sizeof(sc->stats), M_NOWAIT);
281 *((struct ng_async_stat *) resp->data) = sc->stats;
283 case NGM_ASYNC_CMD_CLR_STATS:
284 bzero(&sc->stats, sizeof(sc->stats));
286 case NGM_ASYNC_CMD_SET_CONFIG:
288 struct ng_async_cfg *const cfg =
289 (struct ng_async_cfg *) msg->data;
292 if (msg->header.arglen != sizeof(*cfg))
294 if (cfg->amru < NG_ASYNC_MIN_MRU
295 || cfg->amru > NG_ASYNC_MAX_MRU
296 || cfg->smru < NG_ASYNC_MIN_MRU
297 || cfg->smru > NG_ASYNC_MAX_MRU)
299 cfg->enabled = !!cfg->enabled; /* normalize */
300 if (cfg->smru > sc->cfg.smru) { /* reallocate buffer */
301 buf = malloc(ASYNC_BUF_SIZE(cfg->smru),
302 M_NETGRAPH_ASYNC, M_NOWAIT);
305 free(sc->abuf, M_NETGRAPH_ASYNC);
308 if (cfg->amru > sc->cfg.amru) { /* reallocate buffer */
309 buf = malloc(SYNC_BUF_SIZE(cfg->amru),
310 M_NETGRAPH_ASYNC, M_NOWAIT);
313 free(sc->sbuf, M_NETGRAPH_ASYNC);
315 sc->amode = MODE_HUNT;
319 sc->amode = MODE_HUNT;
325 case NGM_ASYNC_CMD_GET_CONFIG:
326 NG_MKRESPONSE(resp, msg, sizeof(sc->cfg), M_NOWAIT);
329 *((struct ng_async_cfg *) resp->data) = sc->cfg;
339 NG_RESPOND_MSG(error, node, item, resp);
348 nga_shutdown(node_p node)
350 const sc_p sc = NG_NODE_PRIVATE(node);
352 free(sc->abuf, M_NETGRAPH_ASYNC);
353 free(sc->sbuf, M_NETGRAPH_ASYNC);
354 bzero(sc, sizeof(*sc));
355 free(sc, M_NETGRAPH_ASYNC);
356 NG_NODE_SET_PRIVATE(node, NULL);
362 * Lose a hook. When both hooks go away, we disappear.
365 nga_disconnect(hook_p hook)
367 const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
370 if (hook == sc->async)
372 else if (hook == sc->sync)
377 panic("%s 2", __func__);
379 bzero(&sc->stats, sizeof(sc->stats));
381 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
382 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
383 ng_rmnode_self(NG_HOOK_NODE(hook));
387 /******************************************************************
388 INTERNAL HELPER STUFF
389 ******************************************************************/
392 * Encode a byte into the async buffer
395 nga_async_add(const sc_p sc, u_int16_t *fcs, u_int32_t accm, int *len, u_char x)
397 *fcs = PPP_FCS(*fcs, x);
398 if ((x < 32 && ((1 << x) & accm))
400 || (x == PPP_FLAG)) {
401 sc->abuf[(*len)++] = PPP_ESCAPE;
404 sc->abuf[(*len)++] = x;
408 * Receive incoming synchronous data.
411 nga_rcv_sync(const sc_p sc, item_p item)
421 #define ADD_BYTE(x) nga_async_add(sc, &fcs, accm, &alen, (x))
423 /* Check for bypass mode */
424 if (!sc->cfg.enabled) {
425 NG_FWD_ITEM_HOOK(error, item, sc->async );
430 rcvif = m->m_pkthdr.rcvif;
432 /* Get ACCM; special case LCP frames, which use full ACCM */
434 if (m->m_pkthdr.len >= 4) {
435 static const u_char lcphdr[4] = {
438 (u_char)(PPP_LCP >> 8),
439 (u_char)(PPP_LCP & 0xff)
443 m_copydata(m, 0, 4, (caddr_t)buf);
444 if (bcmp(buf, &lcphdr, 4) == 0)
448 /* Check for overflow */
449 if (m->m_pkthdr.len > sc->cfg.smru) {
450 sc->stats.syncOverflows++;
457 sc->stats.syncFrames++;
458 sc->stats.syncOctets += m->m_pkthdr.len;
460 /* Initialize async encoded version of input mbuf */
464 /* Add beginning sync flag if it's been long enough to need one */
466 if (time.tv_sec >= sc->lasttime + 1) {
467 sc->abuf[alen++] = PPP_FLAG;
468 sc->lasttime = time.tv_sec;
471 /* Add packet payload */
473 while (m->m_len > 0) {
474 ADD_BYTE(*mtod(m, u_char *));
481 /* Add checksum and final sync flag */
483 ADD_BYTE(~fcs0 & 0xff);
484 ADD_BYTE(~fcs0 >> 8);
485 sc->abuf[alen++] = PPP_FLAG;
487 /* Put frame in an mbuf and ship it off */
488 if (!(m = m_devget(sc->abuf, alen, 0, rcvif, NULL))) {
492 NG_FWD_NEW_DATA(error, item, sc->async, m);
498 * Receive incoming asynchronous data
499 * XXX Technically, we should strip out incoming characters
500 * that are in our ACCM. Not sure if this is good or not.
503 nga_rcv_async(const sc_p sc, item_p item)
509 if (!sc->cfg.enabled) {
510 NG_FWD_ITEM_HOOK(error, item, sc->sync);
514 rcvif = m->m_pkthdr.rcvif;
518 for (; m->m_len > 0; m->m_data++, m->m_len--) {
519 u_char ch = *mtod(m, u_char *);
521 sc->stats.asyncOctets++;
522 if (ch == PPP_FLAG) { /* Flag overrides everything */
525 /* Check for runts */
528 sc->stats.asyncRunts++;
533 if (sc->fcs != PPP_GOODFCS) {
534 sc->stats.asyncBadCheckSums++;
539 /* Strip address and control fields */
541 && sc->sbuf[0] == PPP_ALLSTATIONS
542 && sc->sbuf[1] == PPP_UI)
545 /* Check for frame too big */
546 if (sc->slen - skip > sc->cfg.amru) {
547 sc->stats.asyncOverflows++;
551 /* OK, ship it out */
552 if ((n = m_devget(sc->sbuf + skip,
553 sc->slen - skip, 0, rcvif, NULL))) {
554 if (item) { /* sets NULL -> item */
555 NG_FWD_NEW_DATA(error, item,
558 NG_SEND_DATA_ONLY(error,
562 sc->stats.asyncFrames++;
564 sc->amode = MODE_NORMAL;
565 sc->fcs = PPP_INITFCS;
571 if (ch == PPP_ESCAPE) {
572 sc->amode = MODE_ESC;
578 sc->amode = MODE_NORMAL;
585 /* Add byte to frame */
586 if (sc->slen >= SYNC_BUF_SIZE(sc->cfg.amru)) {
587 sc->stats.asyncOverflows++;
588 sc->amode = MODE_HUNT;
591 sc->sbuf[sc->slen++] = ch;
592 sc->fcs = PPP_FCS(sc->fcs, ch);
605 * Taken from RFC 1171 Appendix B
607 static const u_int16_t fcstab[256] = {
608 0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
609 0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
610 0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
611 0x9cc9, 0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876,
612 0x2102, 0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd,
613 0xad4a, 0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5,
614 0x3183, 0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c,
615 0xbdcb, 0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974,
616 0x4204, 0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb,
617 0xce4c, 0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3,
618 0x5285, 0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a,
619 0xdecd, 0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72,
620 0x6306, 0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9,
621 0xef4e, 0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1,
622 0x7387, 0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738,
623 0xffcf, 0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70,
624 0x8408, 0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7,
625 0x0840, 0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff,
626 0x9489, 0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036,
627 0x18c1, 0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e,
628 0xa50a, 0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5,
629 0x2942, 0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd,
630 0xb58b, 0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134,
631 0x39c3, 0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c,
632 0xc60c, 0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3,
633 0x4a44, 0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb,
634 0xd68d, 0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232,
635 0x5ac5, 0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a,
636 0xe70e, 0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1,
637 0x6b46, 0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9,
638 0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
639 0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78