| 1 | /* |
| 2 | * ng_pptpgre.c |
| 3 | */ |
| 4 | |
| 5 | /*- |
| 6 | * Copyright (c) 1996-1999 Whistle Communications, Inc. |
| 7 | * All rights reserved. |
| 8 | * |
| 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. |
| 19 | * |
| 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 |
| 36 | * OF SUCH DAMAGE. |
| 37 | * |
| 38 | * Author: Archie Cobbs <archie@freebsd.org> |
| 39 | * |
| 40 | * $FreeBSD: src/sys/netgraph/ng_pptpgre.c,v 1.42 2008/03/26 21:19:03 mav Exp $ |
| 41 | * $DragonFly: src/sys/netgraph7/ng_pptpgre.c,v 1.2 2008/06/26 23:05:35 dillon Exp $ |
| 42 | * $Whistle: ng_pptpgre.c,v 1.7 1999/12/08 00:10:06 archie Exp $ |
| 43 | */ |
| 44 | |
| 45 | /* |
| 46 | * PPTP/GRE netgraph node type. |
| 47 | * |
| 48 | * This node type does the GRE encapsulation as specified for the PPTP |
| 49 | * protocol (RFC 2637, section 4). This includes sequencing and |
| 50 | * retransmission of frames, but not the actual packet delivery nor |
| 51 | * any of the TCP control stream protocol. |
| 52 | * |
| 53 | * The "upper" hook of this node is suitable for attaching to a "ppp" |
| 54 | * node link hook. The "lower" hook of this node is suitable for attaching |
| 55 | * to a "ksocket" node on hook "inet/raw/gre". |
| 56 | */ |
| 57 | |
| 58 | #include <sys/param.h> |
| 59 | #include <sys/systm.h> |
| 60 | #include <sys/kernel.h> |
| 61 | #include <sys/time.h> |
| 62 | #include <sys/lock.h> |
| 63 | #include <sys/malloc.h> |
| 64 | #include <sys/mbuf.h> |
| 65 | #include <sys/mutex.h> |
| 66 | #include <sys/errno.h> |
| 67 | |
| 68 | #include <netinet/in.h> |
| 69 | #include <netinet/in_systm.h> |
| 70 | #include <netinet/ip.h> |
| 71 | |
| 72 | #include "ng_message.h" |
| 73 | #include "netgraph.h" |
| 74 | #include "ng_parse.h" |
| 75 | #include "ng_pptpgre.h" |
| 76 | |
| 77 | /* GRE packet format, as used by PPTP */ |
| 78 | struct greheader { |
| 79 | #if BYTE_ORDER == LITTLE_ENDIAN |
| 80 | u_char recursion:3; /* recursion control */ |
| 81 | u_char ssr:1; /* strict source route */ |
| 82 | u_char hasSeq:1; /* sequence number present */ |
| 83 | u_char hasKey:1; /* key present */ |
| 84 | u_char hasRoute:1; /* routing present */ |
| 85 | u_char hasSum:1; /* checksum present */ |
| 86 | u_char vers:3; /* version */ |
| 87 | u_char flags:4; /* flags */ |
| 88 | u_char hasAck:1; /* acknowlege number present */ |
| 89 | #elif BYTE_ORDER == BIG_ENDIAN |
| 90 | u_char hasSum:1; /* checksum present */ |
| 91 | u_char hasRoute:1; /* routing present */ |
| 92 | u_char hasKey:1; /* key present */ |
| 93 | u_char hasSeq:1; /* sequence number present */ |
| 94 | u_char ssr:1; /* strict source route */ |
| 95 | u_char recursion:3; /* recursion control */ |
| 96 | u_char hasAck:1; /* acknowlege number present */ |
| 97 | u_char flags:4; /* flags */ |
| 98 | u_char vers:3; /* version */ |
| 99 | #else |
| 100 | #error BYTE_ORDER is not defined properly |
| 101 | #endif |
| 102 | u_int16_t proto; /* protocol (ethertype) */ |
| 103 | u_int16_t length; /* payload length */ |
| 104 | u_int16_t cid; /* call id */ |
| 105 | u_int32_t data[0]; /* opt. seq, ack, then data */ |
| 106 | }; |
| 107 | |
| 108 | /* The PPTP protocol ID used in the GRE 'proto' field */ |
| 109 | #define PPTP_GRE_PROTO 0x880b |
| 110 | |
| 111 | /* Bits that must be set a certain way in all PPTP/GRE packets */ |
| 112 | #define PPTP_INIT_VALUE ((0x2001 << 16) | PPTP_GRE_PROTO) |
| 113 | #define PPTP_INIT_MASK 0xef7fffff |
| 114 | |
| 115 | /* Min and max packet length */ |
| 116 | #define PPTP_MAX_PAYLOAD (0xffff - sizeof(struct greheader) - 8) |
| 117 | |
| 118 | /* All times are scaled by this (PPTP_TIME_SCALE time units = 1 sec.) */ |
| 119 | #define PPTP_TIME_SCALE 1024 /* milliseconds */ |
| 120 | typedef u_int64_t pptptime_t; |
| 121 | |
| 122 | /* Acknowledgment timeout parameters and functions */ |
| 123 | #define PPTP_XMIT_WIN 16 /* max xmit window */ |
| 124 | #define PPTP_MIN_TIMEOUT (PPTP_TIME_SCALE / 83) /* 12 milliseconds */ |
| 125 | #define PPTP_MAX_TIMEOUT (3 * PPTP_TIME_SCALE) /* 3 seconds */ |
| 126 | |
| 127 | /* When we recieve a packet, we wait to see if there's an outgoing packet |
| 128 | we can piggy-back the ACK off of. These parameters determine the mimimum |
| 129 | and maxmimum length of time we're willing to wait in order to do that. |
| 130 | These have no effect unless "enableDelayedAck" is turned on. */ |
| 131 | #define PPTP_MIN_ACK_DELAY (PPTP_TIME_SCALE / 500) /* 2 milliseconds */ |
| 132 | #define PPTP_MAX_ACK_DELAY (PPTP_TIME_SCALE / 2) /* 500 milliseconds */ |
| 133 | |
| 134 | /* See RFC 2637 section 4.4 */ |
| 135 | #define PPTP_ACK_ALPHA(x) (((x) + 4) >> 3) /* alpha = 0.125 */ |
| 136 | #define PPTP_ACK_BETA(x) (((x) + 2) >> 2) /* beta = 0.25 */ |
| 137 | #define PPTP_ACK_CHI(x) ((x) << 2) /* chi = 4 */ |
| 138 | #define PPTP_ACK_DELTA(x) ((x) << 1) /* delta = 2 */ |
| 139 | |
| 140 | #define PPTP_SEQ_DIFF(x,y) ((int32_t)(x) - (int32_t)(y)) |
| 141 | |
| 142 | #define SESSHASHSIZE 0x0020 |
| 143 | #define SESSHASH(x) (((x) ^ ((x) >> 8)) & (SESSHASHSIZE - 1)) |
| 144 | |
| 145 | /* We keep packet retransmit and acknowlegement state in this struct */ |
| 146 | struct ng_pptpgre_sess { |
| 147 | node_p node; /* this node pointer */ |
| 148 | hook_p hook; /* hook to upper layers */ |
| 149 | struct ng_pptpgre_conf conf; /* configuration info */ |
| 150 | struct mtx mtx; /* session mutex */ |
| 151 | u_int32_t recvSeq; /* last seq # we rcv'd */ |
| 152 | u_int32_t xmitSeq; /* last seq # we sent */ |
| 153 | u_int32_t recvAck; /* last seq # peer ack'd */ |
| 154 | u_int32_t xmitAck; /* last seq # we ack'd */ |
| 155 | int32_t ato; /* adaptive time-out value */ |
| 156 | int32_t rtt; /* round trip time estimate */ |
| 157 | int32_t dev; /* deviation estimate */ |
| 158 | u_int16_t xmitWin; /* size of xmit window */ |
| 159 | struct callout sackTimer; /* send ack timer */ |
| 160 | struct callout rackTimer; /* recv ack timer */ |
| 161 | u_int32_t winAck; /* seq when xmitWin will grow */ |
| 162 | pptptime_t timeSent[PPTP_XMIT_WIN]; |
| 163 | LIST_ENTRY(ng_pptpgre_sess) sessions; |
| 164 | }; |
| 165 | typedef struct ng_pptpgre_sess *hpriv_p; |
| 166 | |
| 167 | /* Node private data */ |
| 168 | struct ng_pptpgre_private { |
| 169 | hook_p upper; /* hook to upper layers */ |
| 170 | hook_p lower; /* hook to lower layers */ |
| 171 | struct ng_pptpgre_sess uppersess; /* default session for compat */ |
| 172 | LIST_HEAD(, ng_pptpgre_sess) sesshash[SESSHASHSIZE]; |
| 173 | struct ng_pptpgre_stats stats; /* node statistics */ |
| 174 | }; |
| 175 | typedef struct ng_pptpgre_private *priv_p; |
| 176 | |
| 177 | /* Netgraph node methods */ |
| 178 | static ng_constructor_t ng_pptpgre_constructor; |
| 179 | static ng_rcvmsg_t ng_pptpgre_rcvmsg; |
| 180 | static ng_shutdown_t ng_pptpgre_shutdown; |
| 181 | static ng_newhook_t ng_pptpgre_newhook; |
| 182 | static ng_rcvdata_t ng_pptpgre_rcvdata; |
| 183 | static ng_rcvdata_t ng_pptpgre_rcvdata_lower; |
| 184 | static ng_disconnect_t ng_pptpgre_disconnect; |
| 185 | |
| 186 | /* Helper functions */ |
| 187 | static int ng_pptpgre_xmit(hpriv_p hpriv, item_p item); |
| 188 | static void ng_pptpgre_start_send_ack_timer(hpriv_p hpriv); |
| 189 | static void ng_pptpgre_start_recv_ack_timer(hpriv_p hpriv); |
| 190 | static void ng_pptpgre_recv_ack_timeout(node_p node, hook_p hook, |
| 191 | void *arg1, int arg2); |
| 192 | static void ng_pptpgre_send_ack_timeout(node_p node, hook_p hook, |
| 193 | void *arg1, int arg2); |
| 194 | static hpriv_p ng_pptpgre_find_session(priv_p privp, u_int16_t cid); |
| 195 | static void ng_pptpgre_reset(hpriv_p hpriv); |
| 196 | static pptptime_t ng_pptpgre_time(void); |
| 197 | |
| 198 | /* Parse type for struct ng_pptpgre_conf */ |
| 199 | static const struct ng_parse_struct_field ng_pptpgre_conf_type_fields[] |
| 200 | = NG_PPTPGRE_CONF_TYPE_INFO; |
| 201 | static const struct ng_parse_type ng_pptpgre_conf_type = { |
| 202 | &ng_parse_struct_type, |
| 203 | &ng_pptpgre_conf_type_fields, |
| 204 | }; |
| 205 | |
| 206 | /* Parse type for struct ng_pptpgre_stats */ |
| 207 | static const struct ng_parse_struct_field ng_pptpgre_stats_type_fields[] |
| 208 | = NG_PPTPGRE_STATS_TYPE_INFO; |
| 209 | static const struct ng_parse_type ng_pptp_stats_type = { |
| 210 | &ng_parse_struct_type, |
| 211 | &ng_pptpgre_stats_type_fields |
| 212 | }; |
| 213 | |
| 214 | /* List of commands and how to convert arguments to/from ASCII */ |
| 215 | static const struct ng_cmdlist ng_pptpgre_cmdlist[] = { |
| 216 | { |
| 217 | NGM_PPTPGRE_COOKIE, |
| 218 | NGM_PPTPGRE_SET_CONFIG, |
| 219 | "setconfig", |
| 220 | &ng_pptpgre_conf_type, |
| 221 | NULL |
| 222 | }, |
| 223 | { |
| 224 | NGM_PPTPGRE_COOKIE, |
| 225 | NGM_PPTPGRE_GET_CONFIG, |
| 226 | "getconfig", |
| 227 | &ng_parse_hint16_type, |
| 228 | &ng_pptpgre_conf_type |
| 229 | }, |
| 230 | { |
| 231 | NGM_PPTPGRE_COOKIE, |
| 232 | NGM_PPTPGRE_GET_STATS, |
| 233 | "getstats", |
| 234 | NULL, |
| 235 | &ng_pptp_stats_type |
| 236 | }, |
| 237 | { |
| 238 | NGM_PPTPGRE_COOKIE, |
| 239 | NGM_PPTPGRE_CLR_STATS, |
| 240 | "clrstats", |
| 241 | NULL, |
| 242 | NULL |
| 243 | }, |
| 244 | { |
| 245 | NGM_PPTPGRE_COOKIE, |
| 246 | NGM_PPTPGRE_GETCLR_STATS, |
| 247 | "getclrstats", |
| 248 | NULL, |
| 249 | &ng_pptp_stats_type |
| 250 | }, |
| 251 | { 0 } |
| 252 | }; |
| 253 | |
| 254 | /* Node type descriptor */ |
| 255 | static struct ng_type ng_pptpgre_typestruct = { |
| 256 | .version = NG_ABI_VERSION, |
| 257 | .name = NG_PPTPGRE_NODE_TYPE, |
| 258 | .constructor = ng_pptpgre_constructor, |
| 259 | .rcvmsg = ng_pptpgre_rcvmsg, |
| 260 | .shutdown = ng_pptpgre_shutdown, |
| 261 | .newhook = ng_pptpgre_newhook, |
| 262 | .rcvdata = ng_pptpgre_rcvdata, |
| 263 | .disconnect = ng_pptpgre_disconnect, |
| 264 | .cmdlist = ng_pptpgre_cmdlist, |
| 265 | }; |
| 266 | NETGRAPH_INIT(pptpgre, &ng_pptpgre_typestruct); |
| 267 | |
| 268 | #define ERROUT(x) do { error = (x); goto done; } while (0) |
| 269 | |
| 270 | /************************************************************************ |
| 271 | NETGRAPH NODE STUFF |
| 272 | ************************************************************************/ |
| 273 | |
| 274 | /* |
| 275 | * Node type constructor |
| 276 | */ |
| 277 | static int |
| 278 | ng_pptpgre_constructor(node_p node) |
| 279 | { |
| 280 | priv_p priv; |
| 281 | int i; |
| 282 | |
| 283 | /* Allocate private structure */ |
| 284 | priv = kmalloc(sizeof(*priv), M_NETGRAPH, |
| 285 | M_WAITOK | M_NULLOK | M_ZERO); |
| 286 | if (priv == NULL) |
| 287 | return (ENOMEM); |
| 288 | |
| 289 | NG_NODE_SET_PRIVATE(node, priv); |
| 290 | |
| 291 | /* Initialize state */ |
| 292 | mtx_init(&priv->uppersess.mtx, "ng_pptp", NULL, MTX_DEF); |
| 293 | ng_callout_init(&priv->uppersess.sackTimer); |
| 294 | ng_callout_init(&priv->uppersess.rackTimer); |
| 295 | priv->uppersess.node = node; |
| 296 | |
| 297 | for (i = 0; i < SESSHASHSIZE; i++) |
| 298 | LIST_INIT(&priv->sesshash[i]); |
| 299 | |
| 300 | LIST_INSERT_HEAD(&priv->sesshash[0], &priv->uppersess, sessions); |
| 301 | |
| 302 | /* Done */ |
| 303 | return (0); |
| 304 | } |
| 305 | |
| 306 | /* |
| 307 | * Give our OK for a hook to be added. |
| 308 | */ |
| 309 | static int |
| 310 | ng_pptpgre_newhook(node_p node, hook_p hook, const char *name) |
| 311 | { |
| 312 | const priv_p priv = NG_NODE_PRIVATE(node); |
| 313 | |
| 314 | /* Check hook name */ |
| 315 | if (strcmp(name, NG_PPTPGRE_HOOK_UPPER) == 0) { |
| 316 | priv->upper = hook; |
| 317 | priv->uppersess.hook = hook; |
| 318 | NG_HOOK_SET_PRIVATE(hook, &priv->uppersess); |
| 319 | } else if (strcmp(name, NG_PPTPGRE_HOOK_LOWER) == 0) { |
| 320 | priv->lower = hook; |
| 321 | NG_HOOK_SET_RCVDATA(hook, ng_pptpgre_rcvdata_lower); |
| 322 | } else { |
| 323 | static const char hexdig[16] = "0123456789abcdef"; |
| 324 | const char *hex; |
| 325 | hpriv_p hpriv; |
| 326 | int i, j; |
| 327 | uint16_t cid, hash; |
| 328 | |
| 329 | /* Parse hook name to get session ID */ |
| 330 | if (strncmp(name, NG_PPTPGRE_HOOK_SESSION_P, |
| 331 | sizeof(NG_PPTPGRE_HOOK_SESSION_P) - 1) != 0) |
| 332 | return (EINVAL); |
| 333 | hex = name + sizeof(NG_PPTPGRE_HOOK_SESSION_P) - 1; |
| 334 | for (cid = i = 0; i < 4; i++) { |
| 335 | for (j = 0; j < 16 && hex[i] != hexdig[j]; j++); |
| 336 | if (j == 16) |
| 337 | return (EINVAL); |
| 338 | cid = (cid << 4) | j; |
| 339 | } |
| 340 | if (hex[i] != '\0') |
| 341 | return (EINVAL); |
| 342 | |
| 343 | hpriv = kmalloc(sizeof(*hpriv), M_NETGRAPH, M_WAITOK | M_NULLOK | M_ZERO); |
| 344 | if (hpriv == NULL) |
| 345 | return (ENOMEM); |
| 346 | |
| 347 | /* Initialize state */ |
| 348 | mtx_init(&hpriv->mtx, "ng_pptp", NULL, MTX_DEF); |
| 349 | ng_callout_init(&hpriv->sackTimer); |
| 350 | ng_callout_init(&hpriv->rackTimer); |
| 351 | hpriv->conf.cid = cid; |
| 352 | hpriv->node = node; |
| 353 | hpriv->hook = hook; |
| 354 | NG_HOOK_SET_PRIVATE(hook, hpriv); |
| 355 | |
| 356 | hash = SESSHASH(cid); |
| 357 | LIST_INSERT_HEAD(&priv->sesshash[hash], hpriv, sessions); |
| 358 | } |
| 359 | |
| 360 | return (0); |
| 361 | } |
| 362 | |
| 363 | /* |
| 364 | * Receive a control message. |
| 365 | */ |
| 366 | static int |
| 367 | ng_pptpgre_rcvmsg(node_p node, item_p item, hook_p lasthook) |
| 368 | { |
| 369 | const priv_p priv = NG_NODE_PRIVATE(node); |
| 370 | struct ng_mesg *resp = NULL; |
| 371 | int error = 0; |
| 372 | struct ng_mesg *msg; |
| 373 | |
| 374 | NGI_GET_MSG(item, msg); |
| 375 | switch (msg->header.typecookie) { |
| 376 | case NGM_PPTPGRE_COOKIE: |
| 377 | switch (msg->header.cmd) { |
| 378 | case NGM_PPTPGRE_SET_CONFIG: |
| 379 | { |
| 380 | struct ng_pptpgre_conf *const newConf = |
| 381 | (struct ng_pptpgre_conf *) msg->data; |
| 382 | hpriv_p hpriv; |
| 383 | uint16_t hash; |
| 384 | |
| 385 | /* Check for invalid or illegal config */ |
| 386 | if (msg->header.arglen != sizeof(*newConf)) |
| 387 | ERROUT(EINVAL); |
| 388 | /* Try to find session by cid. */ |
| 389 | hpriv = ng_pptpgre_find_session(priv, newConf->cid); |
| 390 | /* If not present - use upper. */ |
| 391 | if (hpriv == NULL) { |
| 392 | hpriv = &priv->uppersess; |
| 393 | LIST_REMOVE(hpriv, sessions); |
| 394 | hash = SESSHASH(newConf->cid); |
| 395 | LIST_INSERT_HEAD(&priv->sesshash[hash], hpriv, |
| 396 | sessions); |
| 397 | } |
| 398 | ng_pptpgre_reset(hpriv); /* reset on configure */ |
| 399 | hpriv->conf = *newConf; |
| 400 | break; |
| 401 | } |
| 402 | case NGM_PPTPGRE_GET_CONFIG: |
| 403 | { |
| 404 | hpriv_p hpriv; |
| 405 | |
| 406 | if (msg->header.arglen == 2) { |
| 407 | /* Try to find session by cid. */ |
| 408 | hpriv = ng_pptpgre_find_session(priv, |
| 409 | *((uint16_t *)msg->data)); |
| 410 | if (hpriv == NULL) |
| 411 | ERROUT(EINVAL); |
| 412 | } else if (msg->header.arglen == 0) { |
| 413 | /* Use upper. */ |
| 414 | hpriv = &priv->uppersess; |
| 415 | } else |
| 416 | ERROUT(EINVAL); |
| 417 | NG_MKRESPONSE(resp, msg, sizeof(hpriv->conf), M_WAITOK | M_NULLOK); |
| 418 | if (resp == NULL) |
| 419 | ERROUT(ENOMEM); |
| 420 | bcopy(&hpriv->conf, resp->data, sizeof(hpriv->conf)); |
| 421 | break; |
| 422 | } |
| 423 | case NGM_PPTPGRE_GET_STATS: |
| 424 | case NGM_PPTPGRE_CLR_STATS: |
| 425 | case NGM_PPTPGRE_GETCLR_STATS: |
| 426 | { |
| 427 | if (msg->header.cmd != NGM_PPTPGRE_CLR_STATS) { |
| 428 | NG_MKRESPONSE(resp, msg, |
| 429 | sizeof(priv->stats), M_WAITOK | M_NULLOK); |
| 430 | if (resp == NULL) |
| 431 | ERROUT(ENOMEM); |
| 432 | bcopy(&priv->stats, |
| 433 | resp->data, sizeof(priv->stats)); |
| 434 | } |
| 435 | if (msg->header.cmd != NGM_PPTPGRE_GET_STATS) |
| 436 | bzero(&priv->stats, sizeof(priv->stats)); |
| 437 | break; |
| 438 | } |
| 439 | default: |
| 440 | error = EINVAL; |
| 441 | break; |
| 442 | } |
| 443 | break; |
| 444 | default: |
| 445 | error = EINVAL; |
| 446 | break; |
| 447 | } |
| 448 | done: |
| 449 | NG_RESPOND_MSG(error, node, item, resp); |
| 450 | NG_FREE_MSG(msg); |
| 451 | return (error); |
| 452 | } |
| 453 | |
| 454 | /* |
| 455 | * Receive incoming data on a hook. |
| 456 | */ |
| 457 | static int |
| 458 | ng_pptpgre_rcvdata(hook_p hook, item_p item) |
| 459 | { |
| 460 | const hpriv_p hpriv = NG_HOOK_PRIVATE(hook); |
| 461 | int rval; |
| 462 | |
| 463 | /* If not configured, reject */ |
| 464 | if (!hpriv->conf.enabled) { |
| 465 | NG_FREE_ITEM(item); |
| 466 | return (ENXIO); |
| 467 | } |
| 468 | |
| 469 | mtx_lock(&hpriv->mtx); |
| 470 | |
| 471 | rval = ng_pptpgre_xmit(hpriv, item); |
| 472 | |
| 473 | mtx_assert(&hpriv->mtx, MA_NOTOWNED); |
| 474 | |
| 475 | return (rval); |
| 476 | } |
| 477 | |
| 478 | /* |
| 479 | * Hook disconnection |
| 480 | */ |
| 481 | static int |
| 482 | ng_pptpgre_disconnect(hook_p hook) |
| 483 | { |
| 484 | const node_p node = NG_HOOK_NODE(hook); |
| 485 | const priv_p priv = NG_NODE_PRIVATE(node); |
| 486 | const hpriv_p hpriv = NG_HOOK_PRIVATE(hook); |
| 487 | |
| 488 | /* Zero out hook pointer */ |
| 489 | if (hook == priv->upper) { |
| 490 | priv->upper = NULL; |
| 491 | priv->uppersess.hook = NULL; |
| 492 | } else if (hook == priv->lower) { |
| 493 | priv->lower = NULL; |
| 494 | } else { |
| 495 | /* Reset node (stops timers) */ |
| 496 | ng_pptpgre_reset(hpriv); |
| 497 | |
| 498 | LIST_REMOVE(hpriv, sessions); |
| 499 | mtx_destroy(&hpriv->mtx); |
| 500 | kfree(hpriv, M_NETGRAPH); |
| 501 | } |
| 502 | |
| 503 | /* Go away if no longer connected to anything */ |
| 504 | if ((NG_NODE_NUMHOOKS(node) == 0) |
| 505 | && (NG_NODE_IS_VALID(node))) |
| 506 | ng_rmnode_self(node); |
| 507 | return (0); |
| 508 | } |
| 509 | |
| 510 | /* |
| 511 | * Destroy node |
| 512 | */ |
| 513 | static int |
| 514 | ng_pptpgre_shutdown(node_p node) |
| 515 | { |
| 516 | const priv_p priv = NG_NODE_PRIVATE(node); |
| 517 | |
| 518 | /* Reset node (stops timers) */ |
| 519 | ng_pptpgre_reset(&priv->uppersess); |
| 520 | |
| 521 | LIST_REMOVE(&priv->uppersess, sessions); |
| 522 | mtx_destroy(&priv->uppersess.mtx); |
| 523 | |
| 524 | kfree(priv, M_NETGRAPH); |
| 525 | |
| 526 | /* Decrement ref count */ |
| 527 | NG_NODE_UNREF(node); |
| 528 | return (0); |
| 529 | } |
| 530 | |
| 531 | /************************************************************************* |
| 532 | TRANSMIT AND RECEIVE FUNCTIONS |
| 533 | *************************************************************************/ |
| 534 | |
| 535 | /* |
| 536 | * Transmit an outgoing frame, or just an ack if m is NULL. |
| 537 | */ |
| 538 | static int |
| 539 | ng_pptpgre_xmit(hpriv_p hpriv, item_p item) |
| 540 | { |
| 541 | const priv_p priv = NG_NODE_PRIVATE(hpriv->node); |
| 542 | u_char buf[sizeof(struct greheader) + 2 * sizeof(u_int32_t)]; |
| 543 | struct greheader *const gre = (struct greheader *)buf; |
| 544 | int grelen, error; |
| 545 | struct mbuf *m; |
| 546 | |
| 547 | mtx_assert(&hpriv->mtx, MA_OWNED); |
| 548 | |
| 549 | if (item) { |
| 550 | NGI_GET_M(item, m); |
| 551 | } else { |
| 552 | m = NULL; |
| 553 | } |
| 554 | /* Check if there's data */ |
| 555 | if (m != NULL) { |
| 556 | |
| 557 | /* Check if windowing is enabled */ |
| 558 | if (hpriv->conf.enableWindowing) { |
| 559 | /* Is our transmit window full? */ |
| 560 | if ((u_int32_t)PPTP_SEQ_DIFF(hpriv->xmitSeq, |
| 561 | hpriv->recvAck) >= hpriv->xmitWin) { |
| 562 | priv->stats.xmitDrops++; |
| 563 | ERROUT(ENOBUFS); |
| 564 | } |
| 565 | } |
| 566 | |
| 567 | /* Sanity check frame length */ |
| 568 | if (m != NULL && m->m_pkthdr.len > PPTP_MAX_PAYLOAD) { |
| 569 | priv->stats.xmitTooBig++; |
| 570 | ERROUT(EMSGSIZE); |
| 571 | } |
| 572 | } else { |
| 573 | priv->stats.xmitLoneAcks++; |
| 574 | } |
| 575 | |
| 576 | /* Build GRE header */ |
| 577 | ((u_int32_t *)gre)[0] = htonl(PPTP_INIT_VALUE); |
| 578 | gre->length = (m != NULL) ? htons((u_short)m->m_pkthdr.len) : 0; |
| 579 | gre->cid = htons(hpriv->conf.peerCid); |
| 580 | |
| 581 | /* Include sequence number if packet contains any data */ |
| 582 | if (m != NULL) { |
| 583 | gre->hasSeq = 1; |
| 584 | if (hpriv->conf.enableWindowing) { |
| 585 | hpriv->timeSent[hpriv->xmitSeq - hpriv->recvAck] |
| 586 | = ng_pptpgre_time(); |
| 587 | } |
| 588 | hpriv->xmitSeq++; |
| 589 | gre->data[0] = htonl(hpriv->xmitSeq); |
| 590 | } |
| 591 | |
| 592 | /* Include acknowledgement (and stop send ack timer) if needed */ |
| 593 | if (hpriv->conf.enableAlwaysAck || hpriv->xmitAck != hpriv->recvSeq) { |
| 594 | gre->hasAck = 1; |
| 595 | gre->data[gre->hasSeq] = htonl(hpriv->recvSeq); |
| 596 | hpriv->xmitAck = hpriv->recvSeq; |
| 597 | if (hpriv->conf.enableDelayedAck) |
| 598 | ng_uncallout(&hpriv->sackTimer, hpriv->node); |
| 599 | } |
| 600 | |
| 601 | /* Prepend GRE header to outgoing frame */ |
| 602 | grelen = sizeof(*gre) + sizeof(u_int32_t) * (gre->hasSeq + gre->hasAck); |
| 603 | if (m == NULL) { |
| 604 | MGETHDR(m, MB_DONTWAIT, MT_DATA); |
| 605 | if (m == NULL) { |
| 606 | priv->stats.memoryFailures++; |
| 607 | ERROUT(ENOBUFS); |
| 608 | } |
| 609 | m->m_len = m->m_pkthdr.len = grelen; |
| 610 | m->m_pkthdr.rcvif = NULL; |
| 611 | } else { |
| 612 | M_PREPEND(m, grelen, MB_DONTWAIT); |
| 613 | if (m == NULL || (m->m_len < grelen |
| 614 | && (m = m_pullup(m, grelen)) == NULL)) { |
| 615 | priv->stats.memoryFailures++; |
| 616 | ERROUT(ENOBUFS); |
| 617 | } |
| 618 | } |
| 619 | bcopy(gre, mtod(m, u_char *), grelen); |
| 620 | |
| 621 | /* Update stats */ |
| 622 | priv->stats.xmitPackets++; |
| 623 | priv->stats.xmitOctets += m->m_pkthdr.len; |
| 624 | |
| 625 | /* |
| 626 | * XXX: we should reset timer only after an item has been sent |
| 627 | * successfully. |
| 628 | */ |
| 629 | if (hpriv->conf.enableWindowing && |
| 630 | gre->hasSeq && hpriv->xmitSeq == hpriv->recvAck + 1) |
| 631 | ng_pptpgre_start_recv_ack_timer(hpriv); |
| 632 | |
| 633 | mtx_unlock(&hpriv->mtx); |
| 634 | |
| 635 | /* Deliver packet */ |
| 636 | if (item) { |
| 637 | NG_FWD_NEW_DATA(error, item, priv->lower, m); |
| 638 | } else { |
| 639 | NG_SEND_DATA_ONLY(error, priv->lower, m); |
| 640 | } |
| 641 | |
| 642 | return (error); |
| 643 | |
| 644 | done: |
| 645 | mtx_unlock(&hpriv->mtx); |
| 646 | NG_FREE_M(m); |
| 647 | if (item) |
| 648 | NG_FREE_ITEM(item); |
| 649 | return (error); |
| 650 | } |
| 651 | |
| 652 | /* |
| 653 | * Handle an incoming packet. The packet includes the IP header. |
| 654 | */ |
| 655 | static int |
| 656 | ng_pptpgre_rcvdata_lower(hook_p hook, item_p item) |
| 657 | { |
| 658 | hpriv_p hpriv; |
| 659 | node_p node = NG_HOOK_NODE(hook); |
| 660 | const priv_p priv = NG_NODE_PRIVATE(node); |
| 661 | int iphlen, grelen, extralen; |
| 662 | const struct greheader *gre; |
| 663 | const struct ip *ip; |
| 664 | int error = 0; |
| 665 | struct mbuf *m; |
| 666 | |
| 667 | NGI_GET_M(item, m); |
| 668 | /* Update stats */ |
| 669 | priv->stats.recvPackets++; |
| 670 | priv->stats.recvOctets += m->m_pkthdr.len; |
| 671 | |
| 672 | /* Sanity check packet length */ |
| 673 | if (m->m_pkthdr.len < sizeof(*ip) + sizeof(*gre)) { |
| 674 | priv->stats.recvRunts++; |
| 675 | ERROUT(EINVAL); |
| 676 | } |
| 677 | |
| 678 | /* Safely pull up the complete IP+GRE headers */ |
| 679 | if (m->m_len < sizeof(*ip) + sizeof(*gre) |
| 680 | && (m = m_pullup(m, sizeof(*ip) + sizeof(*gre))) == NULL) { |
| 681 | priv->stats.memoryFailures++; |
| 682 | ERROUT(ENOBUFS); |
| 683 | } |
| 684 | ip = mtod(m, const struct ip *); |
| 685 | iphlen = ip->ip_hl << 2; |
| 686 | if (m->m_len < iphlen + sizeof(*gre)) { |
| 687 | if ((m = m_pullup(m, iphlen + sizeof(*gre))) == NULL) { |
| 688 | priv->stats.memoryFailures++; |
| 689 | ERROUT(ENOBUFS); |
| 690 | } |
| 691 | ip = mtod(m, const struct ip *); |
| 692 | } |
| 693 | gre = (const struct greheader *)((const u_char *)ip + iphlen); |
| 694 | grelen = sizeof(*gre) + sizeof(u_int32_t) * (gre->hasSeq + gre->hasAck); |
| 695 | if (m->m_pkthdr.len < iphlen + grelen) { |
| 696 | priv->stats.recvRunts++; |
| 697 | ERROUT(EINVAL); |
| 698 | } |
| 699 | if (m->m_len < iphlen + grelen) { |
| 700 | if ((m = m_pullup(m, iphlen + grelen)) == NULL) { |
| 701 | priv->stats.memoryFailures++; |
| 702 | ERROUT(ENOBUFS); |
| 703 | } |
| 704 | ip = mtod(m, const struct ip *); |
| 705 | gre = (const struct greheader *)((const u_char *)ip + iphlen); |
| 706 | } |
| 707 | |
| 708 | /* Sanity check packet length and GRE header bits */ |
| 709 | extralen = m->m_pkthdr.len |
| 710 | - (iphlen + grelen + gre->hasSeq * (u_int16_t)ntohs(gre->length)); |
| 711 | if (extralen < 0) { |
| 712 | priv->stats.recvBadGRE++; |
| 713 | ERROUT(EINVAL); |
| 714 | } |
| 715 | if ((ntohl(*((const u_int32_t *)gre)) & PPTP_INIT_MASK) |
| 716 | != PPTP_INIT_VALUE) { |
| 717 | priv->stats.recvBadGRE++; |
| 718 | ERROUT(EINVAL); |
| 719 | } |
| 720 | |
| 721 | hpriv = ng_pptpgre_find_session(priv, ntohs(gre->cid)); |
| 722 | if (hpriv == NULL || hpriv->hook == NULL || !hpriv->conf.enabled) { |
| 723 | priv->stats.recvBadCID++; |
| 724 | ERROUT(EINVAL); |
| 725 | } |
| 726 | mtx_lock(&hpriv->mtx); |
| 727 | |
| 728 | /* Look for peer ack */ |
| 729 | if (gre->hasAck) { |
| 730 | const u_int32_t ack = ntohl(gre->data[gre->hasSeq]); |
| 731 | const int index = ack - hpriv->recvAck - 1; |
| 732 | long sample; |
| 733 | long diff; |
| 734 | |
| 735 | /* Sanity check ack value */ |
| 736 | if (PPTP_SEQ_DIFF(ack, hpriv->xmitSeq) > 0) { |
| 737 | priv->stats.recvBadAcks++; |
| 738 | goto badAck; /* we never sent it! */ |
| 739 | } |
| 740 | if (PPTP_SEQ_DIFF(ack, hpriv->recvAck) <= 0) |
| 741 | goto badAck; /* ack already timed out */ |
| 742 | hpriv->recvAck = ack; |
| 743 | |
| 744 | /* Update adaptive timeout stuff */ |
| 745 | if (hpriv->conf.enableWindowing) { |
| 746 | sample = ng_pptpgre_time() - hpriv->timeSent[index]; |
| 747 | diff = sample - hpriv->rtt; |
| 748 | hpriv->rtt += PPTP_ACK_ALPHA(diff); |
| 749 | if (diff < 0) |
| 750 | diff = -diff; |
| 751 | hpriv->dev += PPTP_ACK_BETA(diff - hpriv->dev); |
| 752 | /* +2 to compensate low precision of int math */ |
| 753 | hpriv->ato = hpriv->rtt + PPTP_ACK_CHI(hpriv->dev + 2); |
| 754 | if (hpriv->ato > PPTP_MAX_TIMEOUT) |
| 755 | hpriv->ato = PPTP_MAX_TIMEOUT; |
| 756 | else if (hpriv->ato < PPTP_MIN_TIMEOUT) |
| 757 | hpriv->ato = PPTP_MIN_TIMEOUT; |
| 758 | |
| 759 | /* Shift packet transmit times in our transmit window */ |
| 760 | bcopy(hpriv->timeSent + index + 1, hpriv->timeSent, |
| 761 | sizeof(*hpriv->timeSent) |
| 762 | * (PPTP_XMIT_WIN - (index + 1))); |
| 763 | |
| 764 | /* If we sent an entire window, increase window size */ |
| 765 | if (PPTP_SEQ_DIFF(ack, hpriv->winAck) >= 0 |
| 766 | && hpriv->xmitWin < PPTP_XMIT_WIN) { |
| 767 | hpriv->xmitWin++; |
| 768 | hpriv->winAck = ack + hpriv->xmitWin; |
| 769 | } |
| 770 | |
| 771 | /* Stop/(re)start receive ACK timer as necessary */ |
| 772 | ng_uncallout(&hpriv->rackTimer, hpriv->node); |
| 773 | if (hpriv->recvAck != hpriv->xmitSeq) |
| 774 | ng_pptpgre_start_recv_ack_timer(hpriv); |
| 775 | } |
| 776 | } |
| 777 | badAck: |
| 778 | |
| 779 | /* See if frame contains any data */ |
| 780 | if (gre->hasSeq) { |
| 781 | const u_int32_t seq = ntohl(gre->data[0]); |
| 782 | |
| 783 | /* Sanity check sequence number */ |
| 784 | if (PPTP_SEQ_DIFF(seq, hpriv->recvSeq) <= 0) { |
| 785 | if (seq == hpriv->recvSeq) |
| 786 | priv->stats.recvDuplicates++; |
| 787 | else |
| 788 | priv->stats.recvOutOfOrder++; |
| 789 | mtx_unlock(&hpriv->mtx); |
| 790 | ERROUT(EINVAL); |
| 791 | } |
| 792 | hpriv->recvSeq = seq; |
| 793 | |
| 794 | /* We need to acknowledge this packet; do it soon... */ |
| 795 | if (!(callout_pending(&hpriv->sackTimer))) { |
| 796 | /* If delayed ACK is disabled, send it now */ |
| 797 | if (!hpriv->conf.enableDelayedAck) { /* ack now */ |
| 798 | ng_pptpgre_xmit(hpriv, NULL); |
| 799 | /* ng_pptpgre_xmit() drops the mutex */ |
| 800 | } else { /* ack later */ |
| 801 | ng_pptpgre_start_send_ack_timer(hpriv); |
| 802 | mtx_unlock(&hpriv->mtx); |
| 803 | } |
| 804 | } else |
| 805 | mtx_unlock(&hpriv->mtx); |
| 806 | |
| 807 | /* Trim mbuf down to internal payload */ |
| 808 | m_adj(m, iphlen + grelen); |
| 809 | if (extralen > 0) |
| 810 | m_adj(m, -extralen); |
| 811 | |
| 812 | mtx_assert(&hpriv->mtx, MA_NOTOWNED); |
| 813 | |
| 814 | /* Deliver frame to upper layers */ |
| 815 | NG_FWD_NEW_DATA(error, item, hpriv->hook, m); |
| 816 | } else { |
| 817 | priv->stats.recvLoneAcks++; |
| 818 | mtx_unlock(&hpriv->mtx); |
| 819 | NG_FREE_ITEM(item); |
| 820 | NG_FREE_M(m); /* no data to deliver */ |
| 821 | } |
| 822 | |
| 823 | return (error); |
| 824 | |
| 825 | done: |
| 826 | NG_FREE_ITEM(item); |
| 827 | NG_FREE_M(m); |
| 828 | return (error); |
| 829 | } |
| 830 | |
| 831 | /************************************************************************* |
| 832 | TIMER RELATED FUNCTIONS |
| 833 | *************************************************************************/ |
| 834 | |
| 835 | /* |
| 836 | * Start a timer for the peer's acknowledging our oldest unacknowledged |
| 837 | * sequence number. If we get an ack for this sequence number before |
| 838 | * the timer goes off, we cancel the timer. Resets currently running |
| 839 | * recv ack timer, if any. |
| 840 | */ |
| 841 | static void |
| 842 | ng_pptpgre_start_recv_ack_timer(hpriv_p hpriv) |
| 843 | { |
| 844 | int remain, ticks; |
| 845 | |
| 846 | /* Compute how long until oldest unack'd packet times out, |
| 847 | and reset the timer to that time. */ |
| 848 | remain = (hpriv->timeSent[0] + hpriv->ato) - ng_pptpgre_time(); |
| 849 | if (remain < 0) |
| 850 | remain = 0; |
| 851 | |
| 852 | /* Be conservative: timeout can happen up to 1 tick early */ |
| 853 | ticks = (((remain * hz) + PPTP_TIME_SCALE - 1) / PPTP_TIME_SCALE) + 1; |
| 854 | ng_callout(&hpriv->rackTimer, hpriv->node, hpriv->hook, |
| 855 | ticks, ng_pptpgre_recv_ack_timeout, hpriv, 0); |
| 856 | } |
| 857 | |
| 858 | /* |
| 859 | * The peer has failed to acknowledge the oldest unacknowledged sequence |
| 860 | * number within the time allotted. Update our adaptive timeout parameters |
| 861 | * and reset/restart the recv ack timer. |
| 862 | */ |
| 863 | static void |
| 864 | ng_pptpgre_recv_ack_timeout(node_p node, hook_p hook, void *arg1, int arg2) |
| 865 | { |
| 866 | const priv_p priv = NG_NODE_PRIVATE(node); |
| 867 | const hpriv_p hpriv = arg1; |
| 868 | |
| 869 | /* Update adaptive timeout stuff */ |
| 870 | priv->stats.recvAckTimeouts++; |
| 871 | hpriv->rtt = PPTP_ACK_DELTA(hpriv->rtt) + 1; /* +1 to avoid delta*0 case */ |
| 872 | hpriv->ato = hpriv->rtt + PPTP_ACK_CHI(hpriv->dev); |
| 873 | if (hpriv->ato > PPTP_MAX_TIMEOUT) |
| 874 | hpriv->ato = PPTP_MAX_TIMEOUT; |
| 875 | else if (hpriv->ato < PPTP_MIN_TIMEOUT) |
| 876 | hpriv->ato = PPTP_MIN_TIMEOUT; |
| 877 | |
| 878 | /* Reset ack and sliding window */ |
| 879 | hpriv->recvAck = hpriv->xmitSeq; /* pretend we got the ack */ |
| 880 | hpriv->xmitWin = (hpriv->xmitWin + 1) / 2; /* shrink transmit window */ |
| 881 | hpriv->winAck = hpriv->recvAck + hpriv->xmitWin; /* reset win expand time */ |
| 882 | } |
| 883 | |
| 884 | /* |
| 885 | * Start the send ack timer. This assumes the timer is not |
| 886 | * already running. |
| 887 | */ |
| 888 | static void |
| 889 | ng_pptpgre_start_send_ack_timer(hpriv_p hpriv) |
| 890 | { |
| 891 | int ackTimeout, ticks; |
| 892 | |
| 893 | /* Take 1/4 of the estimated round trip time */ |
| 894 | ackTimeout = (hpriv->rtt >> 2); |
| 895 | if (ackTimeout < PPTP_MIN_ACK_DELAY) |
| 896 | ackTimeout = PPTP_MIN_ACK_DELAY; |
| 897 | else if (ackTimeout > PPTP_MAX_ACK_DELAY) |
| 898 | ackTimeout = PPTP_MAX_ACK_DELAY; |
| 899 | |
| 900 | /* Be conservative: timeout can happen up to 1 tick early */ |
| 901 | ticks = (((ackTimeout * hz) + PPTP_TIME_SCALE - 1) / PPTP_TIME_SCALE); |
| 902 | ng_callout(&hpriv->sackTimer, hpriv->node, hpriv->hook, |
| 903 | ticks, ng_pptpgre_send_ack_timeout, hpriv, 0); |
| 904 | } |
| 905 | |
| 906 | /* |
| 907 | * We've waited as long as we're willing to wait before sending an |
| 908 | * acknowledgement to the peer for received frames. We had hoped to |
| 909 | * be able to piggy back our acknowledgement on an outgoing data frame, |
| 910 | * but apparently there haven't been any since. So send the ack now. |
| 911 | */ |
| 912 | static void |
| 913 | ng_pptpgre_send_ack_timeout(node_p node, hook_p hook, void *arg1, int arg2) |
| 914 | { |
| 915 | const hpriv_p hpriv = arg1; |
| 916 | |
| 917 | mtx_lock(&hpriv->mtx); |
| 918 | /* Send a frame with an ack but no payload */ |
| 919 | ng_pptpgre_xmit(hpriv, NULL); |
| 920 | mtx_assert(&hpriv->mtx, MA_NOTOWNED); |
| 921 | } |
| 922 | |
| 923 | /************************************************************************* |
| 924 | MISC FUNCTIONS |
| 925 | *************************************************************************/ |
| 926 | |
| 927 | /* |
| 928 | * Find the hook with a given session ID. |
| 929 | */ |
| 930 | static hpriv_p |
| 931 | ng_pptpgre_find_session(priv_p privp, u_int16_t cid) |
| 932 | { |
| 933 | uint16_t hash = SESSHASH(cid); |
| 934 | hpriv_p hpriv = NULL; |
| 935 | |
| 936 | LIST_FOREACH(hpriv, &privp->sesshash[hash], sessions) { |
| 937 | if (hpriv->conf.cid == cid) |
| 938 | break; |
| 939 | } |
| 940 | |
| 941 | return (hpriv); |
| 942 | } |
| 943 | |
| 944 | /* |
| 945 | * Reset state (must be called with lock held or from writer) |
| 946 | */ |
| 947 | static void |
| 948 | ng_pptpgre_reset(hpriv_p hpriv) |
| 949 | { |
| 950 | /* Reset adaptive timeout state */ |
| 951 | hpriv->ato = PPTP_MAX_TIMEOUT; |
| 952 | hpriv->rtt = PPTP_TIME_SCALE / 10; |
| 953 | if (hpriv->conf.peerPpd > 1) /* ppd = 0 treat as = 1 */ |
| 954 | hpriv->rtt *= hpriv->conf.peerPpd; |
| 955 | hpriv->dev = 0; |
| 956 | hpriv->xmitWin = (hpriv->conf.recvWin + 1) / 2; |
| 957 | if (hpriv->xmitWin < 2) /* often the first packet is lost */ |
| 958 | hpriv->xmitWin = 2; /* because the peer isn't ready */ |
| 959 | else if (hpriv->xmitWin > PPTP_XMIT_WIN) |
| 960 | hpriv->xmitWin = PPTP_XMIT_WIN; |
| 961 | hpriv->winAck = hpriv->xmitWin; |
| 962 | |
| 963 | /* Reset sequence numbers */ |
| 964 | hpriv->recvSeq = ~0; |
| 965 | hpriv->recvAck = ~0; |
| 966 | hpriv->xmitSeq = ~0; |
| 967 | hpriv->xmitAck = ~0; |
| 968 | |
| 969 | /* Stop timers */ |
| 970 | ng_uncallout(&hpriv->sackTimer, hpriv->node); |
| 971 | ng_uncallout(&hpriv->rackTimer, hpriv->node); |
| 972 | } |
| 973 | |
| 974 | /* |
| 975 | * Return the current time scaled & translated to our internally used format. |
| 976 | */ |
| 977 | static pptptime_t |
| 978 | ng_pptpgre_time(void) |
| 979 | { |
| 980 | struct timeval tv; |
| 981 | pptptime_t t; |
| 982 | |
| 983 | microuptime(&tv); |
| 984 | t = (pptptime_t)tv.tv_sec * PPTP_TIME_SCALE; |
| 985 | t += tv.tv_usec / (1000000 / PPTP_TIME_SCALE); |
| 986 | return(t); |
| 987 | } |