| 1 | /* $NetBSD: if_sl.c,v 1.127 2016/10/02 14:17:07 christos Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (c) 1987, 1989, 1992, 1993 |
| 5 | * The Regents of the University of California. All rights reserved. |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * 1. Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in the |
| 14 | * documentation and/or other materials provided with the distribution. |
| 15 | * 3. Neither the name of the University nor the names of its contributors |
| 16 | * may be used to endorse or promote products derived from this software |
| 17 | * without specific prior written permission. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 20 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 21 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 22 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 23 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 24 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 25 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 26 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 27 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 28 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 29 | * SUCH DAMAGE. |
| 30 | * |
| 31 | * @(#)if_sl.c 8.9 (Berkeley) 1/9/95 |
| 32 | */ |
| 33 | |
| 34 | /* |
| 35 | * Serial Line interface |
| 36 | * |
| 37 | * Rick Adams |
| 38 | * Center for Seismic Studies |
| 39 | * 1300 N 17th Street, Suite 1450 |
| 40 | * Arlington, Virginia 22209 |
| 41 | * (703)276-7900 |
| 42 | * rick@seismo.ARPA |
| 43 | * seismo!rick |
| 44 | * |
| 45 | * Pounded on heavily by Chris Torek (chris@mimsy.umd.edu, umcp-cs!chris). |
| 46 | * N.B.: this belongs in netinet, not net, the way it stands now. |
| 47 | * Should have a link-layer type designation, but wouldn't be |
| 48 | * backwards-compatible. |
| 49 | * |
| 50 | * Converted to 4.3BSD Beta by Chris Torek. |
| 51 | * Other changes made at Berkeley, based in part on code by Kirk Smith. |
| 52 | * W. Jolitz added slip abort. |
| 53 | * |
| 54 | * Hacked almost beyond recognition by Van Jacobson (van@helios.ee.lbl.gov). |
| 55 | * Added priority queuing for "interactive" traffic; hooks for TCP |
| 56 | * header compression; ICMP filtering (at 2400 baud, some cretin |
| 57 | * pinging you can use up all your bandwidth). Made low clist behavior |
| 58 | * more robust and slightly less likely to hang serial line. |
| 59 | * Sped up a bunch of things. |
| 60 | */ |
| 61 | |
| 62 | #include <sys/cdefs.h> |
| 63 | __KERNEL_RCSID(0, "$NetBSD: if_sl.c,v 1.127 2016/10/02 14:17:07 christos Exp $" ); |
| 64 | |
| 65 | #ifdef _KERNEL_OPT |
| 66 | #include "opt_inet.h" |
| 67 | #endif |
| 68 | |
| 69 | #include <sys/param.h> |
| 70 | #include <sys/proc.h> |
| 71 | #include <sys/malloc.h> |
| 72 | #include <sys/mbuf.h> |
| 73 | #include <sys/buf.h> |
| 74 | #include <sys/dkstat.h> |
| 75 | #include <sys/socket.h> |
| 76 | #include <sys/ioctl.h> |
| 77 | #include <sys/file.h> |
| 78 | #include <sys/conf.h> |
| 79 | #include <sys/tty.h> |
| 80 | #include <sys/kernel.h> |
| 81 | #include <sys/socketvar.h> |
| 82 | #if __NetBSD__ |
| 83 | #include <sys/systm.h> |
| 84 | #include <sys/kauth.h> |
| 85 | #endif |
| 86 | #include <sys/cpu.h> |
| 87 | #include <sys/intr.h> |
| 88 | #include <sys/device.h> |
| 89 | #include <sys/module.h> |
| 90 | |
| 91 | #include <net/if.h> |
| 92 | #include <net/if_types.h> |
| 93 | #include <net/netisr.h> |
| 94 | #include <net/route.h> |
| 95 | |
| 96 | #ifdef INET |
| 97 | #include <netinet/in.h> |
| 98 | #include <netinet/in_systm.h> |
| 99 | #include <netinet/in_var.h> |
| 100 | #include <netinet/ip.h> |
| 101 | #endif |
| 102 | |
| 103 | #include <net/slcompress.h> |
| 104 | #include <net/if_slvar.h> |
| 105 | #include <net/slip.h> |
| 106 | #include <net/ppp_defs.h> |
| 107 | #include <net/if_ppp.h> |
| 108 | |
| 109 | #include <sys/time.h> |
| 110 | #include <net/bpf.h> |
| 111 | |
| 112 | #include "ioconf.h" |
| 113 | |
| 114 | /* |
| 115 | * SLMAX is a hard limit on input packet size. To simplify the code |
| 116 | * and improve performance, we require that packets fit in an mbuf |
| 117 | * cluster, and if we get a compressed packet, there's enough extra |
| 118 | * room to expand the header into a max length tcp/ip header (128 |
| 119 | * bytes). So, SLMAX can be at most |
| 120 | * MCLBYTES - 128 |
| 121 | * |
| 122 | * SLMTU is a hard limit on output packet size. To insure good |
| 123 | * interactive response, SLMTU wants to be the smallest size that |
| 124 | * amortizes the header cost. (Remember that even with |
| 125 | * type-of-service queuing, we have to wait for any in-progress |
| 126 | * packet to finish. I.e., we wait, on the average, 1/2 * mtu / |
| 127 | * cps, where cps is the line speed in characters per second. |
| 128 | * E.g., 533ms wait for a 1024 byte MTU on a 9600 baud line. The |
| 129 | * average compressed header size is 6-8 bytes so any MTU > 90 |
| 130 | * bytes will give us 90% of the line bandwidth. A 100ms wait is |
| 131 | * tolerable (500ms is not), so want an MTU around 296. (Since TCP |
| 132 | * will send 256 byte segments (to allow for 40 byte headers), the |
| 133 | * typical packet size on the wire will be around 260 bytes). In |
| 134 | * 4.3tahoe+ systems, we can set an MTU in a route so we do that & |
| 135 | * leave the interface MTU relatively high (so we don't IP fragment |
| 136 | * when acting as a gateway to someone using a stupid MTU). |
| 137 | * |
| 138 | * Similar considerations apply to SLIP_HIWAT: It's the amount of |
| 139 | * data that will be queued 'downstream' of us (i.e., in clists |
| 140 | * waiting to be picked up by the tty output interrupt). If we |
| 141 | * queue a lot of data downstream, it's immune to our t.o.s. queuing. |
| 142 | * E.g., if SLIP_HIWAT is 1024, the interactive traffic in mixed |
| 143 | * telnet/ftp will see a 1 sec wait, independent of the mtu (the |
| 144 | * wait is dependent on the ftp window size but that's typically |
| 145 | * 1k - 4k). So, we want SLIP_HIWAT just big enough to amortize |
| 146 | * the cost (in idle time on the wire) of the tty driver running |
| 147 | * off the end of its clists & having to call back slstart for a |
| 148 | * new packet. For a tty interface with any buffering at all, this |
| 149 | * cost will be zero. Even with a totally brain dead interface (like |
| 150 | * the one on a typical workstation), the cost will be <= 1 character |
| 151 | * time. So, setting SLIP_HIWAT to ~100 guarantees that we'll lose |
| 152 | * at most 1% while maintaining good interactive response. |
| 153 | */ |
| 154 | #define BUFOFFSET (128+sizeof(struct ifnet **)+SLIP_HDRLEN) |
| 155 | #define SLMAX (MCLBYTES - BUFOFFSET) |
| 156 | #define SLBUFSIZE (SLMAX + BUFOFFSET) |
| 157 | #ifndef SLMTU |
| 158 | #define SLMTU 296 |
| 159 | #endif |
| 160 | #if (SLMTU < 3) |
| 161 | #error SLMTU way too small. |
| 162 | #endif |
| 163 | #define SLIP_HIWAT roundup(50, TTROUND) |
| 164 | #ifndef __NetBSD__ /* XXX - cgd */ |
| 165 | #define CLISTRESERVE 1024 /* Can't let clists get too low */ |
| 166 | #endif /* !__NetBSD__ */ |
| 167 | |
| 168 | /* |
| 169 | * SLIP ABORT ESCAPE MECHANISM: |
| 170 | * (inspired by HAYES modem escape arrangement) |
| 171 | * 1sec escape 1sec escape 1sec escape { 1sec escape 1sec escape } |
| 172 | * within window time signals a "soft" exit from slip mode by remote end |
| 173 | * if the IFF_DEBUG flag is on. |
| 174 | */ |
| 175 | #define ABT_ESC '\033' /* can't be t_intr - distant host must know it*/ |
| 176 | #define ABT_IDLE 1 /* in seconds - idle before an escape */ |
| 177 | #define ABT_COUNT 3 /* count of escapes for abort */ |
| 178 | #define ABT_WINDOW (ABT_COUNT*2+2) /* in seconds - time to count */ |
| 179 | |
| 180 | static int sl_clone_create(struct if_clone *, int); |
| 181 | static int sl_clone_destroy(struct ifnet *); |
| 182 | |
| 183 | static LIST_HEAD(, sl_softc) sl_softc_list; |
| 184 | |
| 185 | struct if_clone sl_cloner = |
| 186 | IF_CLONE_INITIALIZER("sl" , sl_clone_create, sl_clone_destroy); |
| 187 | |
| 188 | #define FRAME_END 0xc0 /* Frame End */ |
| 189 | #define FRAME_ESCAPE 0xdb /* Frame Esc */ |
| 190 | #define TRANS_FRAME_END 0xdc /* transposed frame end */ |
| 191 | #define TRANS_FRAME_ESCAPE 0xdd /* transposed frame esc */ |
| 192 | |
| 193 | static void slintr(void *); |
| 194 | |
| 195 | static int slcreate(struct sl_softc *); |
| 196 | static struct mbuf *sl_btom(struct sl_softc *, int); |
| 197 | |
| 198 | static int slclose(struct tty *, int); |
| 199 | static int slinput(int, struct tty *); |
| 200 | static int slioctl(struct ifnet *, u_long, void *); |
| 201 | static int slopen(dev_t, struct tty *); |
| 202 | static int sloutput(struct ifnet *, struct mbuf *, const struct sockaddr *, |
| 203 | const struct rtentry *); |
| 204 | static int slstart(struct tty *); |
| 205 | static int sltioctl(struct tty *, u_long, void *, int, struct lwp *); |
| 206 | |
| 207 | static struct linesw slip_disc = { |
| 208 | .l_name = "slip" , |
| 209 | .l_open = slopen, |
| 210 | .l_close = slclose, |
| 211 | .l_read = ttyerrio, |
| 212 | .l_write = ttyerrio, |
| 213 | .l_ioctl = sltioctl, |
| 214 | .l_rint = slinput, |
| 215 | .l_start = slstart, |
| 216 | .l_modem = nullmodem, |
| 217 | .l_poll = ttyerrpoll |
| 218 | }; |
| 219 | |
| 220 | void |
| 221 | slattach(int n __unused) |
| 222 | { |
| 223 | |
| 224 | /* |
| 225 | * Nothing to do here, initialization is handled by the |
| 226 | * module initialization code in slinit() below). |
| 227 | */ |
| 228 | } |
| 229 | |
| 230 | static void |
| 231 | slinit(void) |
| 232 | { |
| 233 | |
| 234 | if (ttyldisc_attach(&slip_disc) != 0) |
| 235 | panic("%s" , __func__); |
| 236 | LIST_INIT(&sl_softc_list); |
| 237 | if_clone_attach(&sl_cloner); |
| 238 | } |
| 239 | |
| 240 | static int |
| 241 | sldetach(void) |
| 242 | { |
| 243 | int error = 0; |
| 244 | |
| 245 | if (!LIST_EMPTY(&sl_softc_list)) |
| 246 | error = EBUSY; |
| 247 | |
| 248 | if (error == 0) |
| 249 | error = ttyldisc_detach(&slip_disc); |
| 250 | |
| 251 | if (error == 0) |
| 252 | if_clone_detach(&sl_cloner); |
| 253 | |
| 254 | return error; |
| 255 | } |
| 256 | |
| 257 | static int |
| 258 | sl_clone_create(struct if_clone *ifc, int unit) |
| 259 | { |
| 260 | struct sl_softc *sc; |
| 261 | |
| 262 | sc = malloc(sizeof(*sc), M_DEVBUF, M_WAIT|M_ZERO); |
| 263 | sc->sc_unit = unit; |
| 264 | if_initname(&sc->sc_if, ifc->ifc_name, unit); |
| 265 | sc->sc_if.if_softc = sc; |
| 266 | sc->sc_if.if_mtu = SLMTU; |
| 267 | sc->sc_if.if_flags = IFF_POINTOPOINT | SC_AUTOCOMP | IFF_MULTICAST; |
| 268 | sc->sc_if.if_type = IFT_SLIP; |
| 269 | sc->sc_if.if_ioctl = slioctl; |
| 270 | sc->sc_if.if_output = sloutput; |
| 271 | sc->sc_if.if_dlt = DLT_SLIP; |
| 272 | sc->sc_fastq.ifq_maxlen = 32; |
| 273 | IFQ_SET_READY(&sc->sc_if.if_snd); |
| 274 | if_attach(&sc->sc_if); |
| 275 | if_alloc_sadl(&sc->sc_if); |
| 276 | bpf_attach(&sc->sc_if, DLT_SLIP, SLIP_HDRLEN); |
| 277 | LIST_INSERT_HEAD(&sl_softc_list, sc, sc_iflist); |
| 278 | return 0; |
| 279 | } |
| 280 | |
| 281 | static int |
| 282 | sl_clone_destroy(struct ifnet *ifp) |
| 283 | { |
| 284 | struct sl_softc *sc = (struct sl_softc *)ifp->if_softc; |
| 285 | |
| 286 | if (sc->sc_ttyp != NULL) |
| 287 | return EBUSY; /* Not removing it */ |
| 288 | |
| 289 | LIST_REMOVE(sc, sc_iflist); |
| 290 | |
| 291 | bpf_detach(ifp); |
| 292 | if_detach(ifp); |
| 293 | |
| 294 | free(sc, M_DEVBUF); |
| 295 | return 0; |
| 296 | } |
| 297 | |
| 298 | static int |
| 299 | slcreate(struct sl_softc *sc) |
| 300 | { |
| 301 | |
| 302 | if (sc->sc_mbuf == NULL) { |
| 303 | sc->sc_mbuf = m_gethdr(M_WAIT, MT_DATA); |
| 304 | m_clget(sc->sc_mbuf, M_WAIT); |
| 305 | } |
| 306 | sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + |
| 307 | sc->sc_mbuf->m_ext.ext_size; |
| 308 | sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + |
| 309 | BUFOFFSET; |
| 310 | |
| 311 | #ifdef INET |
| 312 | sl_compress_init(&sc->sc_comp); |
| 313 | #endif |
| 314 | |
| 315 | return 1; |
| 316 | } |
| 317 | |
| 318 | /* |
| 319 | * Line specific open routine. |
| 320 | * Attach the given tty to the first available sl unit. |
| 321 | */ |
| 322 | /* ARGSUSED */ |
| 323 | static int |
| 324 | slopen(dev_t dev, struct tty *tp) |
| 325 | { |
| 326 | struct lwp *l = curlwp; /* XXX */ |
| 327 | struct sl_softc *sc; |
| 328 | int error; |
| 329 | |
| 330 | error = kauth_authorize_network(l->l_cred, KAUTH_NETWORK_INTERFACE_SLIP, |
| 331 | KAUTH_REQ_NETWORK_INTERFACE_SLIP_ADD, NULL, NULL, NULL); |
| 332 | if (error) |
| 333 | return error; |
| 334 | |
| 335 | if (tp->t_linesw == &slip_disc) |
| 336 | return 0; |
| 337 | |
| 338 | LIST_FOREACH(sc, &sl_softc_list, sc_iflist) |
| 339 | if (sc->sc_ttyp == NULL) { |
| 340 | sc->sc_si = softint_establish(SOFTINT_NET, |
| 341 | slintr, sc); |
| 342 | if (sc->sc_si == NULL) |
| 343 | return ENOMEM; |
| 344 | if (slcreate(sc) == 0) { |
| 345 | softint_disestablish(sc->sc_si); |
| 346 | return ENOBUFS; |
| 347 | } |
| 348 | tp->t_sc = (void *)sc; |
| 349 | sc->sc_ttyp = tp; |
| 350 | sc->sc_if.if_baudrate = tp->t_ospeed; |
| 351 | mutex_spin_enter(&tty_lock); |
| 352 | tp->t_state |= TS_ISOPEN | TS_XCLUDE; |
| 353 | ttyflush(tp, FREAD | FWRITE); |
| 354 | /* |
| 355 | * make sure tty output queue is large enough |
| 356 | * to hold a full-sized packet (including frame |
| 357 | * end, and a possible extra frame end). full-sized |
| 358 | * packet occupies a max of 2*SLMAX bytes (because |
| 359 | * of possible escapes), and add two on for frame |
| 360 | * ends. |
| 361 | */ |
| 362 | if (tp->t_outq.c_cn < 2 * SLMAX + 2) { |
| 363 | sc->sc_oldbufsize = tp->t_outq.c_cn; |
| 364 | sc->sc_oldbufquot = tp->t_outq.c_cq != 0; |
| 365 | |
| 366 | clfree(&tp->t_outq); |
| 367 | mutex_spin_exit(&tty_lock); |
| 368 | error = clalloc(&tp->t_outq, 2 * SLMAX + 2, 0); |
| 369 | if (error) { |
| 370 | softint_disestablish(sc->sc_si); |
| 371 | /* |
| 372 | * clalloc() might return -1 which |
| 373 | * is no good, so we need to return |
| 374 | * something else. |
| 375 | */ |
| 376 | return ENOMEM; /* XXX ?! */ |
| 377 | } |
| 378 | } else { |
| 379 | sc->sc_oldbufsize = sc->sc_oldbufquot = 0; |
| 380 | mutex_spin_exit(&tty_lock); |
| 381 | } |
| 382 | return 0; |
| 383 | } |
| 384 | return ENXIO; |
| 385 | } |
| 386 | |
| 387 | /* |
| 388 | * Line specific close routine. |
| 389 | * Detach the tty from the sl unit. |
| 390 | */ |
| 391 | static int |
| 392 | slclose(struct tty *tp, int flag) |
| 393 | { |
| 394 | struct sl_softc *sc; |
| 395 | int s; |
| 396 | |
| 397 | ttywflush(tp); |
| 398 | sc = tp->t_sc; |
| 399 | |
| 400 | if (sc != NULL) { |
| 401 | softint_disestablish(sc->sc_si); |
| 402 | s = splnet(); |
| 403 | if_down(&sc->sc_if); |
| 404 | IF_PURGE(&sc->sc_fastq); |
| 405 | splx(s); |
| 406 | |
| 407 | s = spltty(); |
| 408 | ttyldisc_release(tp->t_linesw); |
| 409 | tp->t_linesw = ttyldisc_default(); |
| 410 | tp->t_state = 0; |
| 411 | |
| 412 | sc->sc_ttyp = NULL; |
| 413 | tp->t_sc = NULL; |
| 414 | |
| 415 | m_freem(sc->sc_mbuf); |
| 416 | sc->sc_mbuf = NULL; |
| 417 | sc->sc_ep = sc->sc_mp = sc->sc_pktstart = NULL; |
| 418 | IF_PURGE(&sc->sc_inq); |
| 419 | |
| 420 | /* |
| 421 | * If necessary, install a new outq buffer of the |
| 422 | * appropriate size. |
| 423 | */ |
| 424 | if (sc->sc_oldbufsize != 0) { |
| 425 | clfree(&tp->t_outq); |
| 426 | clalloc(&tp->t_outq, sc->sc_oldbufsize, |
| 427 | sc->sc_oldbufquot); |
| 428 | } |
| 429 | splx(s); |
| 430 | } |
| 431 | |
| 432 | return 0; |
| 433 | } |
| 434 | |
| 435 | /* |
| 436 | * Line specific (tty) ioctl routine. |
| 437 | * Provide a way to get the sl unit number. |
| 438 | */ |
| 439 | /* ARGSUSED */ |
| 440 | static int |
| 441 | sltioctl(struct tty *tp, u_long cmd, void *data, int flag, |
| 442 | struct lwp *l) |
| 443 | { |
| 444 | struct sl_softc *sc = (struct sl_softc *)tp->t_sc; |
| 445 | |
| 446 | switch (cmd) { |
| 447 | case SLIOCGUNIT: |
| 448 | *(int *)data = sc->sc_unit; /* XXX */ |
| 449 | break; |
| 450 | |
| 451 | default: |
| 452 | return EPASSTHROUGH; |
| 453 | } |
| 454 | return 0; |
| 455 | } |
| 456 | |
| 457 | /* |
| 458 | * Queue a packet. Start transmission if not active. |
| 459 | * Compression happens in slintr(); if we do it here, IP TOS |
| 460 | * will cause us to not compress "background" packets, because |
| 461 | * ordering gets trashed. It can be done for all packets in slintr(). |
| 462 | */ |
| 463 | static int |
| 464 | sloutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, |
| 465 | const struct rtentry *rtp) |
| 466 | { |
| 467 | struct sl_softc *sc = ifp->if_softc; |
| 468 | struct ip *ip; |
| 469 | struct ifqueue *ifq = NULL; |
| 470 | int s, error; |
| 471 | |
| 472 | IFQ_CLASSIFY(&ifp->if_snd, m, dst->sa_family); |
| 473 | |
| 474 | /* |
| 475 | * `Cannot happen' (see slioctl). Someday we will extend |
| 476 | * the line protocol to support other address families. |
| 477 | */ |
| 478 | if (dst->sa_family != AF_INET) { |
| 479 | printf("%s: af%d not supported\n" , sc->sc_if.if_xname, |
| 480 | dst->sa_family); |
| 481 | m_freem(m); |
| 482 | sc->sc_if.if_noproto++; |
| 483 | return EAFNOSUPPORT; |
| 484 | } |
| 485 | |
| 486 | if (sc->sc_ttyp == NULL) { |
| 487 | m_freem(m); |
| 488 | return ENETDOWN; /* sort of */ |
| 489 | } |
| 490 | if ((sc->sc_ttyp->t_state & TS_CARR_ON) == 0 && |
| 491 | (sc->sc_ttyp->t_cflag & CLOCAL) == 0) { |
| 492 | m_freem(m); |
| 493 | printf("%s: no carrier and not local\n" , sc->sc_if.if_xname); |
| 494 | return EHOSTUNREACH; |
| 495 | } |
| 496 | ip = mtod(m, struct ip *); |
| 497 | #ifdef INET |
| 498 | if (sc->sc_if.if_flags & SC_NOICMP && ip->ip_p == IPPROTO_ICMP) { |
| 499 | m_freem(m); |
| 500 | return ENETRESET; /* XXX ? */ |
| 501 | } |
| 502 | #endif |
| 503 | |
| 504 | s = spltty(); |
| 505 | if (sc->sc_oqlen && sc->sc_ttyp->t_outq.c_cc == sc->sc_oqlen) { |
| 506 | struct bintime bt; |
| 507 | |
| 508 | /* if output's been stalled for too long, and restart */ |
| 509 | getbinuptime(&bt); |
| 510 | bintime_sub(&bt, &sc->sc_lastpacket); |
| 511 | if (bt.sec > 0) { |
| 512 | sc->sc_otimeout++; |
| 513 | slstart(sc->sc_ttyp); |
| 514 | } |
| 515 | } |
| 516 | splx(s); |
| 517 | |
| 518 | s = splnet(); |
| 519 | #ifdef INET |
| 520 | if ((ip->ip_tos & IPTOS_LOWDELAY) != 0) |
| 521 | ifq = &sc->sc_fastq; |
| 522 | #endif |
| 523 | if ((error = ifq_enqueue2(ifp, ifq, m)) != 0) { |
| 524 | splx(s); |
| 525 | return error; |
| 526 | } |
| 527 | getbinuptime(&sc->sc_lastpacket); |
| 528 | splx(s); |
| 529 | |
| 530 | s = spltty(); |
| 531 | if ((sc->sc_oqlen = sc->sc_ttyp->t_outq.c_cc) == 0) |
| 532 | slstart(sc->sc_ttyp); |
| 533 | splx(s); |
| 534 | |
| 535 | return 0; |
| 536 | } |
| 537 | |
| 538 | /* |
| 539 | * Start output on interface. Get another datagram |
| 540 | * to send from the interface queue and map it to |
| 541 | * the interface before starting output. |
| 542 | */ |
| 543 | static int |
| 544 | slstart(struct tty *tp) |
| 545 | { |
| 546 | struct sl_softc *sc = tp->t_sc; |
| 547 | |
| 548 | /* |
| 549 | * If there is more in the output queue, just send it now. |
| 550 | * We are being called in lieu of ttstart and must do what |
| 551 | * it would. |
| 552 | */ |
| 553 | if (tp->t_outq.c_cc != 0) { |
| 554 | (*tp->t_oproc)(tp); |
| 555 | if (tp->t_outq.c_cc > SLIP_HIWAT) |
| 556 | return 0; |
| 557 | } |
| 558 | |
| 559 | /* |
| 560 | * This happens briefly when the line shuts down. |
| 561 | */ |
| 562 | if (sc == NULL) |
| 563 | return 0; |
| 564 | softint_schedule(sc->sc_si); |
| 565 | return 0; |
| 566 | } |
| 567 | |
| 568 | /* |
| 569 | * Copy data buffer to mbuf chain; add ifnet pointer. |
| 570 | */ |
| 571 | static struct mbuf * |
| 572 | sl_btom(struct sl_softc *sc, int len) |
| 573 | { |
| 574 | struct mbuf *m; |
| 575 | |
| 576 | /* |
| 577 | * Allocate a new input buffer and swap. |
| 578 | */ |
| 579 | m = sc->sc_mbuf; |
| 580 | MGETHDR(sc->sc_mbuf, M_DONTWAIT, MT_DATA); |
| 581 | if (sc->sc_mbuf == NULL) { |
| 582 | sc->sc_mbuf = m; |
| 583 | return NULL; |
| 584 | } |
| 585 | MCLGET(sc->sc_mbuf, M_DONTWAIT); |
| 586 | if ((sc->sc_mbuf->m_flags & M_EXT) == 0) { |
| 587 | m_freem(sc->sc_mbuf); |
| 588 | sc->sc_mbuf = m; |
| 589 | return NULL; |
| 590 | } |
| 591 | sc->sc_ep = (u_char *)sc->sc_mbuf->m_ext.ext_buf + |
| 592 | sc->sc_mbuf->m_ext.ext_size; |
| 593 | |
| 594 | m->m_data = sc->sc_pktstart; |
| 595 | |
| 596 | m->m_pkthdr.len = m->m_len = len; |
| 597 | m_set_rcvif(m, &sc->sc_if); |
| 598 | return m; |
| 599 | } |
| 600 | |
| 601 | /* |
| 602 | * tty interface receiver interrupt. |
| 603 | */ |
| 604 | static int |
| 605 | slinput(int c, struct tty *tp) |
| 606 | { |
| 607 | struct sl_softc *sc; |
| 608 | struct mbuf *m; |
| 609 | int len; |
| 610 | |
| 611 | tk_nin++; |
| 612 | sc = (struct sl_softc *)tp->t_sc; |
| 613 | if (sc == NULL) |
| 614 | return 0; |
| 615 | if ((c & TTY_ERRORMASK) || ((tp->t_state & TS_CARR_ON) == 0 && |
| 616 | (tp->t_cflag & CLOCAL) == 0)) { |
| 617 | sc->sc_flags |= SC_ERROR; |
| 618 | return 0; |
| 619 | } |
| 620 | c &= TTY_CHARMASK; |
| 621 | |
| 622 | ++sc->sc_if.if_ibytes; |
| 623 | |
| 624 | if (sc->sc_if.if_flags & IFF_DEBUG) { |
| 625 | if (c == ABT_ESC) { |
| 626 | /* |
| 627 | * If we have a previous abort, see whether |
| 628 | * this one is within the time limit. |
| 629 | */ |
| 630 | if (sc->sc_abortcount && |
| 631 | time_second >= sc->sc_starttime + ABT_WINDOW) |
| 632 | sc->sc_abortcount = 0; |
| 633 | /* |
| 634 | * If we see an abort after "idle" time, count it; |
| 635 | * record when the first abort escape arrived. |
| 636 | */ |
| 637 | if (time_second >= sc->sc_lasttime + ABT_IDLE) { |
| 638 | if (++sc->sc_abortcount == 1) |
| 639 | sc->sc_starttime = time_second; |
| 640 | if (sc->sc_abortcount >= ABT_COUNT) { |
| 641 | slclose(tp, 0); |
| 642 | return 0; |
| 643 | } |
| 644 | } |
| 645 | } else |
| 646 | sc->sc_abortcount = 0; |
| 647 | sc->sc_lasttime = time_second; |
| 648 | } |
| 649 | |
| 650 | switch (c) { |
| 651 | |
| 652 | case TRANS_FRAME_ESCAPE: |
| 653 | if (sc->sc_escape) |
| 654 | c = FRAME_ESCAPE; |
| 655 | break; |
| 656 | |
| 657 | case TRANS_FRAME_END: |
| 658 | if (sc->sc_escape) |
| 659 | c = FRAME_END; |
| 660 | break; |
| 661 | |
| 662 | case FRAME_ESCAPE: |
| 663 | sc->sc_escape = 1; |
| 664 | return 0; |
| 665 | |
| 666 | case FRAME_END: |
| 667 | if (sc->sc_flags & SC_ERROR) { |
| 668 | sc->sc_flags &= ~SC_ERROR; |
| 669 | goto newpack; |
| 670 | } |
| 671 | len = sc->sc_mp - sc->sc_pktstart; |
| 672 | if (len < 3) |
| 673 | /* less than min length packet - ignore */ |
| 674 | goto newpack; |
| 675 | |
| 676 | m = sl_btom(sc, len); |
| 677 | if (m == NULL) |
| 678 | goto error; |
| 679 | |
| 680 | IF_ENQUEUE(&sc->sc_inq, m); |
| 681 | softint_schedule(sc->sc_si); |
| 682 | goto newpack; |
| 683 | } |
| 684 | if (sc->sc_mp < sc->sc_ep) { |
| 685 | *sc->sc_mp++ = c; |
| 686 | sc->sc_escape = 0; |
| 687 | return 0; |
| 688 | } |
| 689 | |
| 690 | /* can't put lower; would miss an extra frame */ |
| 691 | sc->sc_flags |= SC_ERROR; |
| 692 | |
| 693 | error: |
| 694 | sc->sc_if.if_ierrors++; |
| 695 | newpack: |
| 696 | sc->sc_mp = sc->sc_pktstart = (u_char *)sc->sc_mbuf->m_ext.ext_buf + |
| 697 | BUFOFFSET; |
| 698 | sc->sc_escape = 0; |
| 699 | |
| 700 | return 0; |
| 701 | } |
| 702 | |
| 703 | static void |
| 704 | slintr(void *arg) |
| 705 | { |
| 706 | struct sl_softc *sc = arg; |
| 707 | struct tty *tp = sc->sc_ttyp; |
| 708 | struct mbuf *m; |
| 709 | int s, len; |
| 710 | u_char *pktstart; |
| 711 | #ifdef INET |
| 712 | u_char c; |
| 713 | #endif |
| 714 | u_char chdr[CHDR_LEN]; |
| 715 | |
| 716 | KASSERT(tp != NULL); |
| 717 | |
| 718 | /* |
| 719 | * Output processing loop. |
| 720 | */ |
| 721 | mutex_enter(softnet_lock); |
| 722 | for (;;) { |
| 723 | #ifdef INET |
| 724 | struct ip *ip; |
| 725 | #endif |
| 726 | struct mbuf *m2; |
| 727 | struct mbuf *bpf_m; |
| 728 | |
| 729 | /* |
| 730 | * Do not remove the packet from the queue if it |
| 731 | * doesn't look like it will fit into the current |
| 732 | * serial output queue. With a packet full of |
| 733 | * escapes, this could be as bad as MTU*2+2. |
| 734 | */ |
| 735 | s = spltty(); |
| 736 | if (tp->t_outq.c_cn - tp->t_outq.c_cc < |
| 737 | 2 * sc->sc_if.if_mtu + 2) { |
| 738 | splx(s); |
| 739 | break; |
| 740 | } |
| 741 | splx(s); |
| 742 | |
| 743 | /* |
| 744 | * Get a packet and send it to the interface. |
| 745 | */ |
| 746 | s = splnet(); |
| 747 | IF_DEQUEUE(&sc->sc_fastq, m); |
| 748 | if (m) |
| 749 | sc->sc_if.if_omcasts++; /* XXX */ |
| 750 | else |
| 751 | IFQ_DEQUEUE(&sc->sc_if.if_snd, m); |
| 752 | splx(s); |
| 753 | |
| 754 | if (m == NULL) |
| 755 | break; |
| 756 | |
| 757 | /* |
| 758 | * We do the header compression here rather than in |
| 759 | * sloutput() because the packets will be out of order |
| 760 | * if we are using TOS queueing, and the connection |
| 761 | * ID compression will get munged when this happens. |
| 762 | */ |
| 763 | if (sc->sc_if.if_bpf) { |
| 764 | /* |
| 765 | * We need to save the TCP/IP header before |
| 766 | * it's compressed. To avoid complicated |
| 767 | * code, we just make a deep copy of the |
| 768 | * entire packet (since this is a serial |
| 769 | * line, packets should be short and/or the |
| 770 | * copy should be negligible cost compared |
| 771 | * to the packet transmission time). |
| 772 | */ |
| 773 | bpf_m = m_dup(m, 0, M_COPYALL, M_DONTWAIT); |
| 774 | } else |
| 775 | bpf_m = NULL; |
| 776 | #ifdef INET |
| 777 | if ((ip = mtod(m, struct ip *))->ip_p == IPPROTO_TCP) { |
| 778 | if (sc->sc_if.if_flags & SC_COMPRESS) |
| 779 | *mtod(m, u_char *) |= |
| 780 | sl_compress_tcp(m, ip, &sc->sc_comp, 1); |
| 781 | } |
| 782 | #endif |
| 783 | if (bpf_m) |
| 784 | bpf_mtap_sl_out(&sc->sc_if, mtod(m, u_char *), bpf_m); |
| 785 | getbinuptime(&sc->sc_lastpacket); |
| 786 | |
| 787 | s = spltty(); |
| 788 | |
| 789 | /* |
| 790 | * The extra FRAME_END will start up a new packet, |
| 791 | * and thus will flush any accumulated garbage. We |
| 792 | * do this whenever the line may have been idle for |
| 793 | * some time. |
| 794 | */ |
| 795 | if (tp->t_outq.c_cc == 0) { |
| 796 | sc->sc_if.if_obytes++; |
| 797 | (void)putc(FRAME_END, &tp->t_outq); |
| 798 | } |
| 799 | |
| 800 | while (m) { |
| 801 | u_char *bp, *cp, *ep; |
| 802 | |
| 803 | bp = cp = mtod(m, u_char *); |
| 804 | ep = cp + m->m_len; |
| 805 | while (cp < ep) { |
| 806 | /* |
| 807 | * Find out how many bytes in the |
| 808 | * string we can handle without |
| 809 | * doing something special. |
| 810 | */ |
| 811 | while (cp < ep) { |
| 812 | switch (*cp++) { |
| 813 | case FRAME_ESCAPE: |
| 814 | case FRAME_END: |
| 815 | cp--; |
| 816 | goto out; |
| 817 | } |
| 818 | } |
| 819 | out: |
| 820 | if (cp > bp) { |
| 821 | /* |
| 822 | * Put N characters at once |
| 823 | * into the tty output queue. |
| 824 | */ |
| 825 | if (b_to_q(bp, cp - bp, &tp->t_outq)) |
| 826 | break; |
| 827 | sc->sc_if.if_obytes += cp - bp; |
| 828 | } |
| 829 | /* |
| 830 | * If there are characters left in |
| 831 | * the mbuf, the first one must be |
| 832 | * special.. Put it out in a different |
| 833 | * form. |
| 834 | */ |
| 835 | if (cp < ep) { |
| 836 | if (putc(FRAME_ESCAPE, &tp->t_outq)) |
| 837 | break; |
| 838 | if (putc(*cp++ == FRAME_ESCAPE ? |
| 839 | TRANS_FRAME_ESCAPE : |
| 840 | TRANS_FRAME_END, |
| 841 | &tp->t_outq)) { |
| 842 | (void)unputc(&tp->t_outq); |
| 843 | break; |
| 844 | } |
| 845 | sc->sc_if.if_obytes += 2; |
| 846 | } |
| 847 | bp = cp; |
| 848 | } |
| 849 | m = m2 = m_free(m); |
| 850 | } |
| 851 | |
| 852 | if (putc(FRAME_END, &tp->t_outq)) { |
| 853 | /* |
| 854 | * Not enough room. Remove a char to make |
| 855 | * room and end the packet normally. If |
| 856 | * you get many collisions (more than one |
| 857 | * or two a day), you probably do not have |
| 858 | * enough clists and you should increase |
| 859 | * "nclist" in param.c |
| 860 | */ |
| 861 | (void)unputc(&tp->t_outq); |
| 862 | (void)putc(FRAME_END, &tp->t_outq); |
| 863 | sc->sc_if.if_collisions++; |
| 864 | } else { |
| 865 | sc->sc_if.if_obytes++; |
| 866 | sc->sc_if.if_opackets++; |
| 867 | } |
| 868 | |
| 869 | /* |
| 870 | * We now have characters in the output queue, |
| 871 | * kick the serial port. |
| 872 | */ |
| 873 | (*tp->t_oproc)(tp); |
| 874 | splx(s); |
| 875 | } |
| 876 | |
| 877 | /* |
| 878 | * Input processing loop. |
| 879 | */ |
| 880 | for (;;) { |
| 881 | s = spltty(); |
| 882 | IF_DEQUEUE(&sc->sc_inq, m); |
| 883 | splx(s); |
| 884 | if (m == NULL) |
| 885 | break; |
| 886 | pktstart = mtod(m, u_char *); |
| 887 | len = m->m_pkthdr.len; |
| 888 | if (sc->sc_if.if_bpf) { |
| 889 | /* |
| 890 | * Save the compressed header, so we |
| 891 | * can tack it on later. Note that we |
| 892 | * will end up copying garbage in some |
| 893 | * cases but this is okay. We remember |
| 894 | * where the buffer started so we can |
| 895 | * compute the new header length. |
| 896 | */ |
| 897 | memcpy(chdr, pktstart, CHDR_LEN); |
| 898 | } |
| 899 | #ifdef INET |
| 900 | if ((c = (*pktstart & 0xf0)) != (IPVERSION << 4)) { |
| 901 | if (c & 0x80) |
| 902 | c = TYPE_COMPRESSED_TCP; |
| 903 | else if (c == TYPE_UNCOMPRESSED_TCP) |
| 904 | *pktstart &= 0x4f; /* XXX */ |
| 905 | /* |
| 906 | * We've got something that's not an IP |
| 907 | * packet. If compression is enabled, |
| 908 | * try to decompress it. Otherwise, if |
| 909 | * `auto-enable' compression is on and |
| 910 | * it's a reasonable packet, decompress |
| 911 | * it and then enable compression. |
| 912 | * Otherwise, drop it. |
| 913 | */ |
| 914 | if (sc->sc_if.if_flags & SC_COMPRESS) { |
| 915 | len = sl_uncompress_tcp(&pktstart, len, |
| 916 | (u_int)c, &sc->sc_comp); |
| 917 | if (len <= 0) { |
| 918 | m_freem(m); |
| 919 | continue; |
| 920 | } |
| 921 | } else if ((sc->sc_if.if_flags & SC_AUTOCOMP) && |
| 922 | c == TYPE_UNCOMPRESSED_TCP && len >= 40) { |
| 923 | len = sl_uncompress_tcp(&pktstart, len, |
| 924 | (u_int)c, &sc->sc_comp); |
| 925 | if (len <= 0) { |
| 926 | m_freem(m); |
| 927 | continue; |
| 928 | } |
| 929 | sc->sc_if.if_flags |= SC_COMPRESS; |
| 930 | } else { |
| 931 | m_freem(m); |
| 932 | continue; |
| 933 | } |
| 934 | } |
| 935 | #endif |
| 936 | m->m_data = (void *) pktstart; |
| 937 | m->m_pkthdr.len = m->m_len = len; |
| 938 | if (sc->sc_if.if_bpf) { |
| 939 | bpf_mtap_sl_in(&sc->sc_if, chdr, &m); |
| 940 | if (m == NULL) |
| 941 | continue; |
| 942 | } |
| 943 | /* |
| 944 | * If the packet will fit into a single |
| 945 | * header mbuf, copy it into one, to save |
| 946 | * memory. |
| 947 | */ |
| 948 | if (m->m_pkthdr.len < MHLEN) { |
| 949 | struct mbuf *n; |
| 950 | int pktlen; |
| 951 | |
| 952 | MGETHDR(n, M_DONTWAIT, MT_DATA); |
| 953 | pktlen = m->m_pkthdr.len; |
| 954 | M_MOVE_PKTHDR(n, m); |
| 955 | memcpy(mtod(n, void *), mtod(m, void *), pktlen); |
| 956 | n->m_len = m->m_len; |
| 957 | m_freem(m); |
| 958 | m = n; |
| 959 | } |
| 960 | |
| 961 | sc->sc_if.if_ipackets++; |
| 962 | getbinuptime(&sc->sc_lastpacket); |
| 963 | |
| 964 | #ifdef INET |
| 965 | s = splnet(); |
| 966 | if (__predict_false(!pktq_enqueue(ip_pktq, m, 0))) { |
| 967 | sc->sc_if.if_ierrors++; |
| 968 | sc->sc_if.if_iqdrops++; |
| 969 | m_freem(m); |
| 970 | } |
| 971 | splx(s); |
| 972 | #endif |
| 973 | } |
| 974 | mutex_exit(softnet_lock); |
| 975 | } |
| 976 | |
| 977 | /* |
| 978 | * Process an ioctl request. |
| 979 | */ |
| 980 | static int |
| 981 | slioctl(struct ifnet *ifp, u_long cmd, void *data) |
| 982 | { |
| 983 | struct ifaddr *ifa = (struct ifaddr *)data; |
| 984 | struct ifreq *ifr = (struct ifreq *)data; |
| 985 | int s = splnet(), error = 0; |
| 986 | struct sl_softc *sc = ifp->if_softc; |
| 987 | struct ppp_stats *psp; |
| 988 | struct ppp_comp_stats *pcp; |
| 989 | |
| 990 | switch (cmd) { |
| 991 | |
| 992 | case SIOCINITIFADDR: |
| 993 | if (ifa->ifa_addr->sa_family == AF_INET) |
| 994 | ifp->if_flags |= IFF_UP; |
| 995 | else |
| 996 | error = EAFNOSUPPORT; |
| 997 | break; |
| 998 | |
| 999 | case SIOCSIFDSTADDR: |
| 1000 | if (ifa->ifa_addr->sa_family != AF_INET) |
| 1001 | error = EAFNOSUPPORT; |
| 1002 | break; |
| 1003 | |
| 1004 | case SIOCSIFMTU: |
| 1005 | if ((ifr->ifr_mtu < 3) || (ifr->ifr_mtu > SLMAX)) { |
| 1006 | error = EINVAL; |
| 1007 | break; |
| 1008 | } |
| 1009 | /*FALLTHROUGH*/ |
| 1010 | case SIOCGIFMTU: |
| 1011 | if ((error = ifioctl_common(&sc->sc_if, cmd, data)) == ENETRESET) |
| 1012 | error = 0; |
| 1013 | break; |
| 1014 | |
| 1015 | case SIOCADDMULTI: |
| 1016 | case SIOCDELMULTI: |
| 1017 | if (ifr == 0) { |
| 1018 | error = EAFNOSUPPORT; /* XXX */ |
| 1019 | break; |
| 1020 | } |
| 1021 | switch (ifreq_getaddr(cmd, ifr)->sa_family) { |
| 1022 | |
| 1023 | #ifdef INET |
| 1024 | case AF_INET: |
| 1025 | break; |
| 1026 | #endif |
| 1027 | |
| 1028 | default: |
| 1029 | error = EAFNOSUPPORT; |
| 1030 | break; |
| 1031 | } |
| 1032 | break; |
| 1033 | |
| 1034 | case SIOCGPPPSTATS: |
| 1035 | psp = &((struct ifpppstatsreq *) data)->stats; |
| 1036 | (void)memset(psp, 0, sizeof(*psp)); |
| 1037 | psp->p.ppp_ibytes = sc->sc_if.if_ibytes; |
| 1038 | psp->p.ppp_ipackets = sc->sc_if.if_ipackets; |
| 1039 | psp->p.ppp_ierrors = sc->sc_if.if_ierrors; |
| 1040 | psp->p.ppp_obytes = sc->sc_if.if_obytes; |
| 1041 | psp->p.ppp_opackets = sc->sc_if.if_opackets; |
| 1042 | psp->p.ppp_oerrors = sc->sc_if.if_oerrors; |
| 1043 | #ifdef INET |
| 1044 | psp->vj.vjs_packets = sc->sc_comp.sls_packets; |
| 1045 | psp->vj.vjs_compressed = sc->sc_comp.sls_compressed; |
| 1046 | psp->vj.vjs_searches = sc->sc_comp.sls_searches; |
| 1047 | psp->vj.vjs_misses = sc->sc_comp.sls_misses; |
| 1048 | psp->vj.vjs_uncompressedin = sc->sc_comp.sls_uncompressedin; |
| 1049 | psp->vj.vjs_compressedin = sc->sc_comp.sls_compressedin; |
| 1050 | psp->vj.vjs_errorin = sc->sc_comp.sls_errorin; |
| 1051 | psp->vj.vjs_tossed = sc->sc_comp.sls_tossed; |
| 1052 | #endif |
| 1053 | break; |
| 1054 | |
| 1055 | case SIOCGPPPCSTATS: |
| 1056 | pcp = &((struct ifpppcstatsreq *) data)->stats; |
| 1057 | (void)memset(pcp, 0, sizeof(*pcp)); |
| 1058 | break; |
| 1059 | |
| 1060 | default: |
| 1061 | error = ifioctl_common(ifp, cmd, data); |
| 1062 | break; |
| 1063 | } |
| 1064 | splx(s); |
| 1065 | return error; |
| 1066 | } |
| 1067 | |
| 1068 | |
| 1069 | /* |
| 1070 | * Module infrastructure |
| 1071 | */ |
| 1072 | |
| 1073 | #include "if_module.h" |
| 1074 | |
| 1075 | IF_MODULE(MODULE_CLASS_DRIVER, sl, "slcompress" ); |
| 1076 | |