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sys/netgraph/ng_ksocket.c
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1 /* 2 * ng_ksocket.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 * $FreeBSD$ 41 * $Whistle: ng_ksocket.c,v 1.1 1999/11/16 20:04:40 archie Exp $ 42 */ 43 44 /* 45 * Kernel socket node type. This node type is basically a kernel-mode 46 * version of a socket... kindof like the reverse of the socket node type. 47 */ 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/kernel.h> 52 #include <sys/mbuf.h> 53 #include <sys/proc.h> 54 #include <sys/malloc.h> 55 #include <sys/ctype.h> 56 #include <sys/protosw.h> 57 #include <sys/errno.h> 58 #include <sys/socket.h> 59 #include <sys/socketvar.h> 60 #include <sys/uio.h> 61 #include <sys/un.h> 62 63 #include <netgraph/ng_message.h> 64 #include <netgraph/netgraph.h> 65 #include <netgraph/ng_parse.h> 66 #include <netgraph/ng_ksocket.h> 67 68 #include <netinet/in.h> 69 #include <netinet/ip.h> 70 71 #ifdef NG_SEPARATE_MALLOC 72 static MALLOC_DEFINE(M_NETGRAPH_KSOCKET, "netgraph_ksock", 73 "netgraph ksock node"); 74 #else 75 #define M_NETGRAPH_KSOCKET M_NETGRAPH 76 #endif 77 78 #define OFFSETOF(s, e) ((char *)&((s *)0)->e - (char *)((s *)0)) 79 #define SADATA_OFFSET (OFFSETOF(struct sockaddr, sa_data)) 80 81 /* Node private data */ 82 struct ng_ksocket_private { 83 node_p node; 84 hook_p hook; 85 struct socket *so; 86 int fn_sent; /* FN call on incoming event was sent */ 87 LIST_HEAD(, ng_ksocket_private) embryos; 88 LIST_ENTRY(ng_ksocket_private) siblings; 89 u_int32_t flags; 90 u_int32_t response_token; 91 ng_ID_t response_addr; 92 }; 93 typedef struct ng_ksocket_private *priv_p; 94 95 /* Flags for priv_p */ 96 #define KSF_CONNECTING 0x00000001 /* Waiting for connection complete */ 97 #define KSF_ACCEPTING 0x00000002 /* Waiting for accept complete */ 98 #define KSF_EOFSEEN 0x00000004 /* Have sent 0-length EOF mbuf */ 99 #define KSF_CLONED 0x00000008 /* Cloned from an accepting socket */ 100 #define KSF_EMBRYONIC 0x00000010 /* Cloned node with no hooks yet */ 101 102 /* Netgraph node methods */ 103 static ng_constructor_t ng_ksocket_constructor; 104 static ng_rcvmsg_t ng_ksocket_rcvmsg; 105 static ng_shutdown_t ng_ksocket_shutdown; 106 static ng_newhook_t ng_ksocket_newhook; 107 static ng_rcvdata_t ng_ksocket_rcvdata; 108 static ng_connect_t ng_ksocket_connect; 109 static ng_disconnect_t ng_ksocket_disconnect; 110 111 /* Alias structure */ 112 struct ng_ksocket_alias { 113 const char *name; 114 const int value; 115 const int family; 116 }; 117 118 /* Protocol family aliases */ 119 static const struct ng_ksocket_alias ng_ksocket_families[] = { 120 { "local", PF_LOCAL }, 121 { "inet", PF_INET }, 122 { "inet6", PF_INET6 }, 123 { "atm", PF_ATM }, 124 { "divert", PF_DIVERT }, 125 { NULL, -1 }, 126 }; 127 128 /* Socket type aliases */ 129 static const struct ng_ksocket_alias ng_ksocket_types[] = { 130 { "stream", SOCK_STREAM }, 131 { "dgram", SOCK_DGRAM }, 132 { "raw", SOCK_RAW }, 133 { "rdm", SOCK_RDM }, 134 { "seqpacket", SOCK_SEQPACKET }, 135 { NULL, -1 }, 136 }; 137 138 /* Protocol aliases */ 139 static const struct ng_ksocket_alias ng_ksocket_protos[] = { 140 { "ip", IPPROTO_IP, PF_INET }, 141 { "raw", IPPROTO_RAW, PF_INET }, 142 { "icmp", IPPROTO_ICMP, PF_INET }, 143 { "igmp", IPPROTO_IGMP, PF_INET }, 144 { "tcp", IPPROTO_TCP, PF_INET }, 145 { "udp", IPPROTO_UDP, PF_INET }, 146 { "gre", IPPROTO_GRE, PF_INET }, 147 { "esp", IPPROTO_ESP, PF_INET }, 148 { "ah", IPPROTO_AH, PF_INET }, 149 { "swipe", IPPROTO_SWIPE, PF_INET }, 150 { "encap", IPPROTO_ENCAP, PF_INET }, 151 { "pim", IPPROTO_PIM, PF_INET }, 152 { NULL, -1 }, 153 }; 154 155 /* Helper functions */ 156 static int ng_ksocket_accept(priv_p); 157 static int ng_ksocket_incoming(struct socket *so, void *arg, int waitflag); 158 static int ng_ksocket_parse(const struct ng_ksocket_alias *aliases, 159 const char *s, int family); 160 static void ng_ksocket_incoming2(node_p node, hook_p hook, 161 void *arg1, int arg2); 162 163 /************************************************************************ 164 STRUCT SOCKADDR PARSE TYPE 165 ************************************************************************/ 166 167 /* Get the length of the data portion of a generic struct sockaddr */ 168 static int 169 ng_parse_generic_sockdata_getLength(const struct ng_parse_type *type, 170 const u_char *start, const u_char *buf) 171 { 172 const struct sockaddr *sa; 173 174 sa = (const struct sockaddr *)(buf - SADATA_OFFSET); 175 return (sa->sa_len < SADATA_OFFSET) ? 0 : sa->sa_len - SADATA_OFFSET; 176 } 177 178 /* Type for the variable length data portion of a generic struct sockaddr */ 179 static const struct ng_parse_type ng_ksocket_generic_sockdata_type = { 180 &ng_parse_bytearray_type, 181 &ng_parse_generic_sockdata_getLength 182 }; 183 184 /* Type for a generic struct sockaddr */ 185 static const struct ng_parse_struct_field 186 ng_parse_generic_sockaddr_type_fields[] = { 187 { "len", &ng_parse_uint8_type }, 188 { "family", &ng_parse_uint8_type }, 189 { "data", &ng_ksocket_generic_sockdata_type }, 190 { NULL } 191 }; 192 static const struct ng_parse_type ng_ksocket_generic_sockaddr_type = { 193 &ng_parse_struct_type, 194 &ng_parse_generic_sockaddr_type_fields 195 }; 196 197 /* Convert a struct sockaddr from ASCII to binary. If its a protocol 198 family that we specially handle, do that, otherwise defer to the 199 generic parse type ng_ksocket_generic_sockaddr_type. */ 200 static int 201 ng_ksocket_sockaddr_parse(const struct ng_parse_type *type, 202 const char *s, int *off, const u_char *const start, 203 u_char *const buf, int *buflen) 204 { 205 struct sockaddr *const sa = (struct sockaddr *)buf; 206 enum ng_parse_token tok; 207 char fambuf[32]; 208 int family, len; 209 char *t; 210 211 /* If next token is a left curly brace, use generic parse type */ 212 if ((tok = ng_parse_get_token(s, off, &len)) == T_LBRACE) { 213 return (*ng_ksocket_generic_sockaddr_type.supertype->parse) 214 (&ng_ksocket_generic_sockaddr_type, 215 s, off, start, buf, buflen); 216 } 217 218 /* Get socket address family followed by a slash */ 219 while (isspace(s[*off])) 220 (*off)++; 221 if ((t = strchr(s + *off, '/')) == NULL) 222 return (EINVAL); 223 if ((len = t - (s + *off)) > sizeof(fambuf) - 1) 224 return (EINVAL); 225 strncpy(fambuf, s + *off, len); 226 fambuf[len] = '\0'; 227 *off += len + 1; 228 if ((family = ng_ksocket_parse(ng_ksocket_families, fambuf, 0)) == -1) 229 return (EINVAL); 230 231 /* Set family */ 232 if (*buflen < SADATA_OFFSET) 233 return (ERANGE); 234 sa->sa_family = family; 235 236 /* Set family-specific data and length */ 237 switch (sa->sa_family) { 238 case PF_LOCAL: /* Get pathname */ 239 { 240 const int pathoff = OFFSETOF(struct sockaddr_un, sun_path); 241 struct sockaddr_un *const sun = (struct sockaddr_un *)sa; 242 int toklen, pathlen; 243 char *path; 244 245 if ((path = ng_get_string_token(s, off, &toklen, NULL)) == NULL) 246 return (EINVAL); 247 pathlen = strlen(path); 248 if (pathlen > SOCK_MAXADDRLEN) { 249 free(path, M_NETGRAPH_KSOCKET); 250 return (E2BIG); 251 } 252 if (*buflen < pathoff + pathlen) { 253 free(path, M_NETGRAPH_KSOCKET); 254 return (ERANGE); 255 } 256 *off += toklen; 257 bcopy(path, sun->sun_path, pathlen); 258 sun->sun_len = pathoff + pathlen; 259 free(path, M_NETGRAPH_KSOCKET); 260 break; 261 } 262 263 case PF_INET: /* Get an IP address with optional port */ 264 { 265 struct sockaddr_in *const sin = (struct sockaddr_in *)sa; 266 int i; 267 268 /* Parse this: <ipaddress>[:port] */ 269 for (i = 0; i < 4; i++) { 270 u_long val; 271 char *eptr; 272 273 val = strtoul(s + *off, &eptr, 10); 274 if (val > 0xff || eptr == s + *off) 275 return (EINVAL); 276 *off += (eptr - (s + *off)); 277 ((u_char *)&sin->sin_addr)[i] = (u_char)val; 278 if (i < 3) { 279 if (s[*off] != '.') 280 return (EINVAL); 281 (*off)++; 282 } else if (s[*off] == ':') { 283 (*off)++; 284 val = strtoul(s + *off, &eptr, 10); 285 if (val > 0xffff || eptr == s + *off) 286 return (EINVAL); 287 *off += (eptr - (s + *off)); 288 sin->sin_port = htons(val); 289 } else 290 sin->sin_port = 0; 291 } 292 bzero(&sin->sin_zero, sizeof(sin->sin_zero)); 293 sin->sin_len = sizeof(*sin); 294 break; 295 } 296 297 #if 0 298 case PF_INET6: /* XXX implement this someday */ 299 #endif 300 301 default: 302 return (EINVAL); 303 } 304 305 /* Done */ 306 *buflen = sa->sa_len; 307 return (0); 308 } 309 310 /* Convert a struct sockaddr from binary to ASCII */ 311 static int 312 ng_ksocket_sockaddr_unparse(const struct ng_parse_type *type, 313 const u_char *data, int *off, char *cbuf, int cbuflen) 314 { 315 const struct sockaddr *sa = (const struct sockaddr *)(data + *off); 316 int slen = 0; 317 318 /* Output socket address, either in special or generic format */ 319 switch (sa->sa_family) { 320 case PF_LOCAL: 321 { 322 const int pathoff = OFFSETOF(struct sockaddr_un, sun_path); 323 const struct sockaddr_un *sun = (const struct sockaddr_un *)sa; 324 const int pathlen = sun->sun_len - pathoff; 325 char pathbuf[SOCK_MAXADDRLEN + 1]; 326 char *pathtoken; 327 328 bcopy(sun->sun_path, pathbuf, pathlen); 329 if ((pathtoken = ng_encode_string(pathbuf, pathlen)) == NULL) 330 return (ENOMEM); 331 slen += snprintf(cbuf, cbuflen, "local/%s", pathtoken); 332 free(pathtoken, M_NETGRAPH_KSOCKET); 333 if (slen >= cbuflen) 334 return (ERANGE); 335 *off += sun->sun_len; 336 return (0); 337 } 338 339 case PF_INET: 340 { 341 const struct sockaddr_in *sin = (const struct sockaddr_in *)sa; 342 343 slen += snprintf(cbuf, cbuflen, "inet/%d.%d.%d.%d", 344 ((const u_char *)&sin->sin_addr)[0], 345 ((const u_char *)&sin->sin_addr)[1], 346 ((const u_char *)&sin->sin_addr)[2], 347 ((const u_char *)&sin->sin_addr)[3]); 348 if (sin->sin_port != 0) { 349 slen += snprintf(cbuf + strlen(cbuf), 350 cbuflen - strlen(cbuf), ":%d", 351 (u_int)ntohs(sin->sin_port)); 352 } 353 if (slen >= cbuflen) 354 return (ERANGE); 355 *off += sizeof(*sin); 356 return(0); 357 } 358 359 #if 0 360 case PF_INET6: /* XXX implement this someday */ 361 #endif 362 363 default: 364 return (*ng_ksocket_generic_sockaddr_type.supertype->unparse) 365 (&ng_ksocket_generic_sockaddr_type, 366 data, off, cbuf, cbuflen); 367 } 368 } 369 370 /* Parse type for struct sockaddr */ 371 static const struct ng_parse_type ng_ksocket_sockaddr_type = { 372 NULL, 373 NULL, 374 NULL, 375 &ng_ksocket_sockaddr_parse, 376 &ng_ksocket_sockaddr_unparse, 377 NULL /* no such thing as a default struct sockaddr */ 378 }; 379 380 /************************************************************************ 381 STRUCT NG_KSOCKET_SOCKOPT PARSE TYPE 382 ************************************************************************/ 383 384 /* Get length of the struct ng_ksocket_sockopt value field, which is the 385 just the excess of the message argument portion over the length of 386 the struct ng_ksocket_sockopt. */ 387 static int 388 ng_parse_sockoptval_getLength(const struct ng_parse_type *type, 389 const u_char *start, const u_char *buf) 390 { 391 static const int offset = OFFSETOF(struct ng_ksocket_sockopt, value); 392 const struct ng_ksocket_sockopt *sopt; 393 const struct ng_mesg *msg; 394 395 sopt = (const struct ng_ksocket_sockopt *)(buf - offset); 396 msg = (const struct ng_mesg *)((const u_char *)sopt - sizeof(*msg)); 397 return msg->header.arglen - sizeof(*sopt); 398 } 399 400 /* Parse type for the option value part of a struct ng_ksocket_sockopt 401 XXX Eventually, we should handle the different socket options specially. 402 XXX This would avoid byte order problems, eg an integer value of 1 is 403 XXX going to be "[1]" for little endian or "[3=1]" for big endian. */ 404 static const struct ng_parse_type ng_ksocket_sockoptval_type = { 405 &ng_parse_bytearray_type, 406 &ng_parse_sockoptval_getLength 407 }; 408 409 /* Parse type for struct ng_ksocket_sockopt */ 410 static const struct ng_parse_struct_field ng_ksocket_sockopt_type_fields[] 411 = NG_KSOCKET_SOCKOPT_INFO(&ng_ksocket_sockoptval_type); 412 static const struct ng_parse_type ng_ksocket_sockopt_type = { 413 &ng_parse_struct_type, 414 &ng_ksocket_sockopt_type_fields 415 }; 416 417 /* Parse type for struct ng_ksocket_accept */ 418 static const struct ng_parse_struct_field ng_ksocket_accept_type_fields[] 419 = NGM_KSOCKET_ACCEPT_INFO; 420 static const struct ng_parse_type ng_ksocket_accept_type = { 421 &ng_parse_struct_type, 422 &ng_ksocket_accept_type_fields 423 }; 424 425 /* List of commands and how to convert arguments to/from ASCII */ 426 static const struct ng_cmdlist ng_ksocket_cmds[] = { 427 { 428 NGM_KSOCKET_COOKIE, 429 NGM_KSOCKET_BIND, 430 "bind", 431 &ng_ksocket_sockaddr_type, 432 NULL 433 }, 434 { 435 NGM_KSOCKET_COOKIE, 436 NGM_KSOCKET_LISTEN, 437 "listen", 438 &ng_parse_int32_type, 439 NULL 440 }, 441 { 442 NGM_KSOCKET_COOKIE, 443 NGM_KSOCKET_ACCEPT, 444 "accept", 445 NULL, 446 &ng_ksocket_accept_type 447 }, 448 { 449 NGM_KSOCKET_COOKIE, 450 NGM_KSOCKET_CONNECT, 451 "connect", 452 &ng_ksocket_sockaddr_type, 453 &ng_parse_int32_type 454 }, 455 { 456 NGM_KSOCKET_COOKIE, 457 NGM_KSOCKET_GETNAME, 458 "getname", 459 NULL, 460 &ng_ksocket_sockaddr_type 461 }, 462 { 463 NGM_KSOCKET_COOKIE, 464 NGM_KSOCKET_GETPEERNAME, 465 "getpeername", 466 NULL, 467 &ng_ksocket_sockaddr_type 468 }, 469 { 470 NGM_KSOCKET_COOKIE, 471 NGM_KSOCKET_SETOPT, 472 "setopt", 473 &ng_ksocket_sockopt_type, 474 NULL 475 }, 476 { 477 NGM_KSOCKET_COOKIE, 478 NGM_KSOCKET_GETOPT, 479 "getopt", 480 &ng_ksocket_sockopt_type, 481 &ng_ksocket_sockopt_type 482 }, 483 { 0 } 484 }; 485 486 /* Node type descriptor */ 487 static struct ng_type ng_ksocket_typestruct = { 488 .version = NG_ABI_VERSION, 489 .name = NG_KSOCKET_NODE_TYPE, 490 .constructor = ng_ksocket_constructor, 491 .rcvmsg = ng_ksocket_rcvmsg, 492 .shutdown = ng_ksocket_shutdown, 493 .newhook = ng_ksocket_newhook, 494 .connect = ng_ksocket_connect, 495 .rcvdata = ng_ksocket_rcvdata, 496 .disconnect = ng_ksocket_disconnect, 497 .cmdlist = ng_ksocket_cmds, 498 }; 499 NETGRAPH_INIT(ksocket, &ng_ksocket_typestruct); 500 501 #define ERROUT(x) do { error = (x); goto done; } while (0) 502 503 /************************************************************************ 504 NETGRAPH NODE STUFF 505 ************************************************************************/ 506 507 /* 508 * Node type constructor 509 * The NODE part is assumed to be all set up. 510 * There is already a reference to the node for us. 511 */ 512 static int 513 ng_ksocket_constructor(node_p node) 514 { 515 priv_p priv; 516 517 /* Allocate private structure */ 518 priv = malloc(sizeof(*priv), M_NETGRAPH_KSOCKET, M_NOWAIT | M_ZERO); 519 if (priv == NULL) 520 return (ENOMEM); 521 522 LIST_INIT(&priv->embryos); 523 /* cross link them */ 524 priv->node = node; 525 NG_NODE_SET_PRIVATE(node, priv); 526 527 /* Done */ 528 return (0); 529 } 530 531 /* 532 * Give our OK for a hook to be added. The hook name is of the 533 * form "<family>/<type>/<proto>" where the three components may 534 * be decimal numbers or else aliases from the above lists. 535 * 536 * Connecting a hook amounts to opening the socket. Disconnecting 537 * the hook closes the socket and destroys the node as well. 538 */ 539 static int 540 ng_ksocket_newhook(node_p node, hook_p hook, const char *name0) 541 { 542 struct thread *td = curthread; /* XXX broken */ 543 const priv_p priv = NG_NODE_PRIVATE(node); 544 char *s1, *s2, name[NG_HOOKSIZ]; 545 int family, type, protocol, error; 546 547 /* Check if we're already connected */ 548 if (priv->hook != NULL) 549 return (EISCONN); 550 551 if (priv->flags & KSF_CLONED) { 552 if (priv->flags & KSF_EMBRYONIC) { 553 /* Remove ourselves from our parent's embryo list */ 554 LIST_REMOVE(priv, siblings); 555 priv->flags &= ~KSF_EMBRYONIC; 556 } 557 } else { 558 /* Extract family, type, and protocol from hook name */ 559 snprintf(name, sizeof(name), "%s", name0); 560 s1 = name; 561 if ((s2 = strchr(s1, '/')) == NULL) 562 return (EINVAL); 563 *s2++ = '\0'; 564 family = ng_ksocket_parse(ng_ksocket_families, s1, 0); 565 if (family == -1) 566 return (EINVAL); 567 s1 = s2; 568 if ((s2 = strchr(s1, '/')) == NULL) 569 return (EINVAL); 570 *s2++ = '\0'; 571 type = ng_ksocket_parse(ng_ksocket_types, s1, 0); 572 if (type == -1) 573 return (EINVAL); 574 s1 = s2; 575 protocol = ng_ksocket_parse(ng_ksocket_protos, s1, family); 576 if (protocol == -1) 577 return (EINVAL); 578 579 /* Create the socket */ 580 error = socreate(family, &priv->so, type, protocol, 581 td->td_ucred, td); 582 if (error != 0) 583 return (error); 584 585 /* XXX call soreserve() ? */ 586 } 587 588 /* OK */ 589 priv->hook = hook; 590 591 /* 592 * In case of misconfigured routing a packet may reenter 593 * ksocket node recursively. Decouple stack to avoid possible 594 * panics about sleeping with locks held. 595 */ 596 NG_HOOK_FORCE_QUEUE(hook); 597 598 return(0); 599 } 600 601 static int 602 ng_ksocket_connect(hook_p hook) 603 { 604 node_p node = NG_HOOK_NODE(hook); 605 const priv_p priv = NG_NODE_PRIVATE(node); 606 struct socket *const so = priv->so; 607 608 /* Add our hook for incoming data and other events */ 609 SOCKBUF_LOCK(&priv->so->so_rcv); 610 soupcall_set(priv->so, SO_RCV, ng_ksocket_incoming, node); 611 SOCKBUF_UNLOCK(&priv->so->so_rcv); 612 SOCKBUF_LOCK(&priv->so->so_snd); 613 soupcall_set(priv->so, SO_SND, ng_ksocket_incoming, node); 614 SOCKBUF_UNLOCK(&priv->so->so_snd); 615 SOCK_LOCK(priv->so); 616 priv->so->so_state |= SS_NBIO; 617 SOCK_UNLOCK(priv->so); 618 /* 619 * --Original comment-- 620 * On a cloned socket we may have already received one or more 621 * upcalls which we couldn't handle without a hook. Handle 622 * those now. 623 * We cannot call the upcall function directly 624 * from here, because until this function has returned our 625 * hook isn't connected. 626 * 627 * ---meta comment for -current --- 628 * XXX This is dubius. 629 * Upcalls between the time that the hook was 630 * first created and now (on another processesor) will 631 * be earlier on the queue than the request to finalise the hook. 632 * By the time the hook is finalised, 633 * The queued upcalls will have happened and the code 634 * will have discarded them because of a lack of a hook. 635 * (socket not open). 636 * 637 * This is a bad byproduct of the complicated way in which hooks 638 * are now created (3 daisy chained async events). 639 * 640 * Since we are a netgraph operation 641 * We know that we hold a lock on this node. This forces the 642 * request we make below to be queued rather than implemented 643 * immediately which will cause the upcall function to be called a bit 644 * later. 645 * However, as we will run any waiting queued operations immediately 646 * after doing this one, if we have not finalised the other end 647 * of the hook, those queued operations will fail. 648 */ 649 if (priv->flags & KSF_CLONED) { 650 ng_send_fn(node, NULL, &ng_ksocket_incoming2, so, M_NOWAIT); 651 } 652 653 return (0); 654 } 655 656 /* 657 * Receive a control message 658 */ 659 static int 660 ng_ksocket_rcvmsg(node_p node, item_p item, hook_p lasthook) 661 { 662 struct thread *td = curthread; /* XXX broken */ 663 const priv_p priv = NG_NODE_PRIVATE(node); 664 struct socket *const so = priv->so; 665 struct ng_mesg *resp = NULL; 666 int error = 0; 667 struct ng_mesg *msg; 668 669 NGI_GET_MSG(item, msg); 670 switch (msg->header.typecookie) { 671 case NGM_KSOCKET_COOKIE: 672 switch (msg->header.cmd) { 673 case NGM_KSOCKET_BIND: 674 { 675 struct sockaddr *const sa 676 = (struct sockaddr *)msg->data; 677 678 /* Sanity check */ 679 if (msg->header.arglen < SADATA_OFFSET 680 || msg->header.arglen < sa->sa_len) 681 ERROUT(EINVAL); 682 if (so == NULL) 683 ERROUT(ENXIO); 684 685 /* Bind */ 686 error = sobind(so, sa, td); 687 break; 688 } 689 case NGM_KSOCKET_LISTEN: 690 { 691 /* Sanity check */ 692 if (msg->header.arglen != sizeof(int32_t)) 693 ERROUT(EINVAL); 694 if (so == NULL) 695 ERROUT(ENXIO); 696 697 /* Listen */ 698 so->so_state |= SS_NBIO; 699 error = solisten(so, *((int32_t *)msg->data), td); 700 break; 701 } 702 703 case NGM_KSOCKET_ACCEPT: 704 { 705 /* Sanity check */ 706 if (msg->header.arglen != 0) 707 ERROUT(EINVAL); 708 if (so == NULL) 709 ERROUT(ENXIO); 710 711 /* Make sure the socket is capable of accepting */ 712 if (!(so->so_options & SO_ACCEPTCONN)) 713 ERROUT(EINVAL); 714 if (priv->flags & KSF_ACCEPTING) 715 ERROUT(EALREADY); 716 717 /* 718 * If a connection is already complete, take it. 719 * Otherwise let the upcall function deal with 720 * the connection when it comes in. 721 */ 722 error = ng_ksocket_accept(priv); 723 if (error != 0 && error != EWOULDBLOCK) 724 ERROUT(error); 725 priv->response_token = msg->header.token; 726 priv->response_addr = NGI_RETADDR(item); 727 break; 728 } 729 730 case NGM_KSOCKET_CONNECT: 731 { 732 struct sockaddr *const sa 733 = (struct sockaddr *)msg->data; 734 735 /* Sanity check */ 736 if (msg->header.arglen < SADATA_OFFSET 737 || msg->header.arglen < sa->sa_len) 738 ERROUT(EINVAL); 739 if (so == NULL) 740 ERROUT(ENXIO); 741 742 /* Do connect */ 743 if ((so->so_state & SS_ISCONNECTING) != 0) 744 ERROUT(EALREADY); 745 if ((error = soconnect(so, sa, td)) != 0) { 746 so->so_state &= ~SS_ISCONNECTING; 747 ERROUT(error); 748 } 749 if ((so->so_state & SS_ISCONNECTING) != 0) { 750 /* We will notify the sender when we connect */ 751 priv->response_token = msg->header.token; 752 priv->response_addr = NGI_RETADDR(item); 753 priv->flags |= KSF_CONNECTING; 754 ERROUT(EINPROGRESS); 755 } 756 break; 757 } 758 759 case NGM_KSOCKET_GETNAME: 760 case NGM_KSOCKET_GETPEERNAME: 761 { 762 int (*func)(struct socket *so, struct sockaddr **nam); 763 struct sockaddr *sa = NULL; 764 int len; 765 766 /* Sanity check */ 767 if (msg->header.arglen != 0) 768 ERROUT(EINVAL); 769 if (so == NULL) 770 ERROUT(ENXIO); 771 772 /* Get function */ 773 if (msg->header.cmd == NGM_KSOCKET_GETPEERNAME) { 774 if ((so->so_state 775 & (SS_ISCONNECTED|SS_ISCONFIRMING)) == 0) 776 ERROUT(ENOTCONN); 777 func = so->so_proto->pr_peeraddr; 778 } else 779 func = so->so_proto->pr_sockaddr; 780 781 /* Get local or peer address */ 782 if ((error = (*func)(so, &sa)) != 0) 783 goto bail; 784 len = (sa == NULL) ? 0 : sa->sa_len; 785 786 /* Send it back in a response */ 787 NG_MKRESPONSE(resp, msg, len, M_NOWAIT); 788 if (resp == NULL) { 789 error = ENOMEM; 790 goto bail; 791 } 792 bcopy(sa, resp->data, len); 793 794 bail: 795 /* Cleanup */ 796 if (sa != NULL) 797 free(sa, M_SONAME); 798 break; 799 } 800 801 case NGM_KSOCKET_GETOPT: 802 { 803 struct ng_ksocket_sockopt *ksopt = 804 (struct ng_ksocket_sockopt *)msg->data; 805 struct sockopt sopt; 806 807 /* Sanity check */ 808 if (msg->header.arglen != sizeof(*ksopt)) 809 ERROUT(EINVAL); 810 if (so == NULL) 811 ERROUT(ENXIO); 812 813 /* Get response with room for option value */ 814 NG_MKRESPONSE(resp, msg, sizeof(*ksopt) 815 + NG_KSOCKET_MAX_OPTLEN, M_NOWAIT); 816 if (resp == NULL) 817 ERROUT(ENOMEM); 818 819 /* Get socket option, and put value in the response */ 820 sopt.sopt_dir = SOPT_GET; 821 sopt.sopt_level = ksopt->level; 822 sopt.sopt_name = ksopt->name; 823 sopt.sopt_td = NULL; 824 sopt.sopt_valsize = NG_KSOCKET_MAX_OPTLEN; 825 ksopt = (struct ng_ksocket_sockopt *)resp->data; 826 sopt.sopt_val = ksopt->value; 827 if ((error = sogetopt(so, &sopt)) != 0) { 828 NG_FREE_MSG(resp); 829 break; 830 } 831 832 /* Set actual value length */ 833 resp->header.arglen = sizeof(*ksopt) 834 + sopt.sopt_valsize; 835 break; 836 } 837 838 case NGM_KSOCKET_SETOPT: 839 { 840 struct ng_ksocket_sockopt *const ksopt = 841 (struct ng_ksocket_sockopt *)msg->data; 842 const int valsize = msg->header.arglen - sizeof(*ksopt); 843 struct sockopt sopt; 844 845 /* Sanity check */ 846 if (valsize < 0) 847 ERROUT(EINVAL); 848 if (so == NULL) 849 ERROUT(ENXIO); 850 851 /* Set socket option */ 852 sopt.sopt_dir = SOPT_SET; 853 sopt.sopt_level = ksopt->level; 854 sopt.sopt_name = ksopt->name; 855 sopt.sopt_val = ksopt->value; 856 sopt.sopt_valsize = valsize; 857 sopt.sopt_td = NULL; 858 error = sosetopt(so, &sopt); 859 break; 860 } 861 862 default: 863 error = EINVAL; 864 break; 865 } 866 break; 867 default: 868 error = EINVAL; 869 break; 870 } 871 done: 872 NG_RESPOND_MSG(error, node, item, resp); 873 NG_FREE_MSG(msg); 874 return (error); 875 } 876 877 /* 878 * Receive incoming data on our hook. Send it out the socket. 879 */ 880 static int 881 ng_ksocket_rcvdata(hook_p hook, item_p item) 882 { 883 struct thread *td = curthread; /* XXX broken */ 884 const node_p node = NG_HOOK_NODE(hook); 885 const priv_p priv = NG_NODE_PRIVATE(node); 886 struct socket *const so = priv->so; 887 struct sockaddr *sa = NULL; 888 int error; 889 struct mbuf *m; 890 #ifdef ALIGNED_POINTER 891 struct mbuf *n; 892 #endif /* ALIGNED_POINTER */ 893 struct sa_tag *stag; 894 895 /* Extract data */ 896 NGI_GET_M(item, m); 897 NG_FREE_ITEM(item); 898 #ifdef ALIGNED_POINTER 899 if (!ALIGNED_POINTER(mtod(m, caddr_t), uint32_t)) { 900 n = m_defrag(m, M_NOWAIT); 901 if (n == NULL) { 902 m_freem(m); 903 return (ENOBUFS); 904 } 905 m = n; 906 } 907 #endif /* ALIGNED_POINTER */ 908 /* 909 * Look if socket address is stored in packet tags. 910 * If sockaddr is ours, or provided by a third party (zero id), 911 * then we accept it. 912 */ 913 if (((stag = (struct sa_tag *)m_tag_locate(m, NGM_KSOCKET_COOKIE, 914 NG_KSOCKET_TAG_SOCKADDR, NULL)) != NULL) && 915 (stag->id == NG_NODE_ID(node) || stag->id == 0)) 916 sa = &stag->sa; 917 918 /* Reset specific mbuf flags to prevent addressing problems. */ 919 m->m_flags &= ~(M_BCAST|M_MCAST); 920 921 /* Send packet */ 922 error = sosend(so, sa, 0, m, 0, 0, td); 923 924 return (error); 925 } 926 927 /* 928 * Destroy node 929 */ 930 static int 931 ng_ksocket_shutdown(node_p node) 932 { 933 const priv_p priv = NG_NODE_PRIVATE(node); 934 priv_p embryo; 935 936 /* Close our socket (if any) */ 937 if (priv->so != NULL) { 938 SOCKBUF_LOCK(&priv->so->so_rcv); 939 soupcall_clear(priv->so, SO_RCV); 940 SOCKBUF_UNLOCK(&priv->so->so_rcv); 941 SOCKBUF_LOCK(&priv->so->so_snd); 942 soupcall_clear(priv->so, SO_SND); 943 SOCKBUF_UNLOCK(&priv->so->so_snd); 944 soclose(priv->so); 945 priv->so = NULL; 946 } 947 948 /* If we are an embryo, take ourselves out of the parent's list */ 949 if (priv->flags & KSF_EMBRYONIC) { 950 LIST_REMOVE(priv, siblings); 951 priv->flags &= ~KSF_EMBRYONIC; 952 } 953 954 /* Remove any embryonic children we have */ 955 while (!LIST_EMPTY(&priv->embryos)) { 956 embryo = LIST_FIRST(&priv->embryos); 957 ng_rmnode_self(embryo->node); 958 } 959 960 /* Take down netgraph node */ 961 bzero(priv, sizeof(*priv)); 962 free(priv, M_NETGRAPH_KSOCKET); 963 NG_NODE_SET_PRIVATE(node, NULL); 964 NG_NODE_UNREF(node); /* let the node escape */ 965 return (0); 966 } 967 968 /* 969 * Hook disconnection 970 */ 971 static int 972 ng_ksocket_disconnect(hook_p hook) 973 { 974 KASSERT(NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0, 975 ("%s: numhooks=%d?", __func__, 976 NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)))); 977 if (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))) 978 ng_rmnode_self(NG_HOOK_NODE(hook)); 979 return (0); 980 } 981 982 /************************************************************************ 983 HELPER STUFF 984 ************************************************************************/ 985 /* 986 * You should not "just call" a netgraph node function from an external 987 * asynchronous event. This is because in doing so you are ignoring the 988 * locking on the netgraph nodes. Instead call your function via ng_send_fn(). 989 * This will call the function you chose, but will first do all the 990 * locking rigmarole. Your function MAY only be called at some distant future 991 * time (several millisecs away) so don't give it any arguments 992 * that may be revoked soon (e.g. on your stack). 993 * 994 * To decouple stack, we use queue version of ng_send_fn(). 995 */ 996 997 static int 998 ng_ksocket_incoming(struct socket *so, void *arg, int waitflag) 999 { 1000 const node_p node = arg; 1001 const priv_p priv = NG_NODE_PRIVATE(node); 1002 int wait = ((waitflag & M_WAITOK) ? NG_WAITOK : 0) | NG_QUEUE; 1003 1004 /* 1005 * Even if node is not locked, as soon as we are called, we assume 1006 * it exist and it's private area is valid. With some care we can 1007 * access it. Mark node that incoming event for it was sent to 1008 * avoid unneded queue trashing. 1009 */ 1010 if (atomic_cmpset_int(&priv->fn_sent, 0, 1) && 1011 ng_send_fn1(node, NULL, &ng_ksocket_incoming2, so, 0, wait)) { 1012 atomic_store_rel_int(&priv->fn_sent, 0); 1013 } 1014 return (SU_OK); 1015 } 1016 1017 /* 1018 * When incoming data is appended to the socket, we get notified here. 1019 * This is also called whenever a significant event occurs for the socket. 1020 * Our original caller may have queued this even some time ago and 1021 * we cannot trust that he even still exists. The node however is being 1022 * held with a reference by the queueing code and guarantied to be valid. 1023 */ 1024 static void 1025 ng_ksocket_incoming2(node_p node, hook_p hook, void *arg1, int arg2) 1026 { 1027 struct socket *so = arg1; 1028 const priv_p priv = NG_NODE_PRIVATE(node); 1029 struct ng_mesg *response; 1030 int error; 1031 1032 KASSERT(so == priv->so, ("%s: wrong socket", __func__)); 1033 1034 /* Allow next incoming event to be queued. */ 1035 atomic_store_rel_int(&priv->fn_sent, 0); 1036 1037 /* Check whether a pending connect operation has completed */ 1038 if (priv->flags & KSF_CONNECTING) { 1039 if ((error = so->so_error) != 0) { 1040 so->so_error = 0; 1041 so->so_state &= ~SS_ISCONNECTING; 1042 } 1043 if (!(so->so_state & SS_ISCONNECTING)) { 1044 NG_MKMESSAGE(response, NGM_KSOCKET_COOKIE, 1045 NGM_KSOCKET_CONNECT, sizeof(int32_t), M_NOWAIT); 1046 if (response != NULL) { 1047 response->header.flags |= NGF_RESP; 1048 response->header.token = priv->response_token; 1049 *(int32_t *)response->data = error; 1050 /* 1051 * send an async "response" message 1052 * to the node that set us up 1053 * (if it still exists) 1054 */ 1055 NG_SEND_MSG_ID(error, node, 1056 response, priv->response_addr, 0); 1057 } 1058 priv->flags &= ~KSF_CONNECTING; 1059 } 1060 } 1061 1062 /* Check whether a pending accept operation has completed */ 1063 if (priv->flags & KSF_ACCEPTING) 1064 (void )ng_ksocket_accept(priv); 1065 1066 /* 1067 * If we don't have a hook, we must handle data events later. When 1068 * the hook gets created and is connected, this upcall function 1069 * will be called again. 1070 */ 1071 if (priv->hook == NULL) 1072 return; 1073 1074 /* Read and forward available mbufs. */ 1075 while (1) { 1076 struct uio uio; 1077 struct sockaddr *sa; 1078 struct mbuf *m; 1079 int flags; 1080 1081 /* Try to get next packet from socket. */ 1082 uio.uio_td = NULL; 1083 uio.uio_resid = IP_MAXPACKET; 1084 flags = MSG_DONTWAIT; 1085 sa = NULL; 1086 if ((error = soreceive(so, (so->so_state & SS_ISCONNECTED) ? 1087 NULL : &sa, &uio, &m, NULL, &flags)) != 0) 1088 break; 1089 1090 /* See if we got anything. */ 1091 if (flags & MSG_TRUNC) { 1092 m_freem(m); 1093 m = NULL; 1094 } 1095 if (m == NULL) { 1096 if (sa != NULL) 1097 free(sa, M_SONAME); 1098 break; 1099 } 1100 1101 KASSERT(m->m_nextpkt == NULL, ("%s: nextpkt", __func__)); 1102 1103 /* 1104 * Stream sockets do not have packet boundaries, so 1105 * we have to allocate a header mbuf and attach the 1106 * stream of data to it. 1107 */ 1108 if (so->so_type == SOCK_STREAM) { 1109 struct mbuf *mh; 1110 1111 mh = m_gethdr(M_NOWAIT, MT_DATA); 1112 if (mh == NULL) { 1113 m_freem(m); 1114 if (sa != NULL) 1115 free(sa, M_SONAME); 1116 break; 1117 } 1118 1119 mh->m_next = m; 1120 for (; m; m = m->m_next) 1121 mh->m_pkthdr.len += m->m_len; 1122 m = mh; 1123 } 1124 1125 /* Put peer's socket address (if any) into a tag */ 1126 if (sa != NULL) { 1127 struct sa_tag *stag; 1128 1129 stag = (struct sa_tag *)m_tag_alloc(NGM_KSOCKET_COOKIE, 1130 NG_KSOCKET_TAG_SOCKADDR, sizeof(ng_ID_t) + 1131 sa->sa_len, M_NOWAIT); 1132 if (stag == NULL) { 1133 free(sa, M_SONAME); 1134 goto sendit; 1135 } 1136 bcopy(sa, &stag->sa, sa->sa_len); 1137 free(sa, M_SONAME); 1138 stag->id = NG_NODE_ID(node); 1139 m_tag_prepend(m, &stag->tag); 1140 } 1141 1142 sendit: /* Forward data with optional peer sockaddr as packet tag */ 1143 NG_SEND_DATA_ONLY(error, priv->hook, m); 1144 } 1145 1146 /* 1147 * If the peer has closed the connection, forward a 0-length mbuf 1148 * to indicate end-of-file. 1149 */ 1150 if (so->so_rcv.sb_state & SBS_CANTRCVMORE && 1151 !(priv->flags & KSF_EOFSEEN)) { 1152 struct mbuf *m; 1153 1154 m = m_gethdr(M_NOWAIT, MT_DATA); 1155 if (m != NULL) 1156 NG_SEND_DATA_ONLY(error, priv->hook, m); 1157 priv->flags |= KSF_EOFSEEN; 1158 } 1159 } 1160 1161 static int 1162 ng_ksocket_accept(priv_p priv) 1163 { 1164 struct socket *const head = priv->so; 1165 struct socket *so; 1166 struct sockaddr *sa = NULL; 1167 struct ng_mesg *resp; 1168 struct ng_ksocket_accept *resp_data; 1169 node_p node; 1170 priv_p priv2; 1171 int len; 1172 int error; 1173 1174 SOLISTEN_LOCK(head); 1175 error = solisten_dequeue(head, &so, SOCK_NONBLOCK); 1176 if (error == EWOULDBLOCK) { 1177 priv->flags |= KSF_ACCEPTING; 1178 return (error); 1179 } 1180 priv->flags &= ~KSF_ACCEPTING; 1181 if (error) 1182 return (error); 1183 1184 if ((error = soaccept(so, &sa)) != 0) 1185 return (error); 1186 1187 len = OFFSETOF(struct ng_ksocket_accept, addr); 1188 if (sa != NULL) 1189 len += sa->sa_len; 1190 1191 NG_MKMESSAGE(resp, NGM_KSOCKET_COOKIE, NGM_KSOCKET_ACCEPT, len, 1192 M_NOWAIT); 1193 if (resp == NULL) { 1194 soclose(so); 1195 goto out; 1196 } 1197 resp->header.flags |= NGF_RESP; 1198 resp->header.token = priv->response_token; 1199 1200 /* Clone a ksocket node to wrap the new socket */ 1201 error = ng_make_node_common(&ng_ksocket_typestruct, &node); 1202 if (error) { 1203 free(resp, M_NETGRAPH); 1204 soclose(so); 1205 goto out; 1206 } 1207 1208 if (ng_ksocket_constructor(node) != 0) { 1209 NG_NODE_UNREF(node); 1210 free(resp, M_NETGRAPH); 1211 soclose(so); 1212 goto out; 1213 } 1214 1215 priv2 = NG_NODE_PRIVATE(node); 1216 priv2->so = so; 1217 priv2->flags |= KSF_CLONED | KSF_EMBRYONIC; 1218 1219 /* 1220 * Insert the cloned node into a list of embryonic children 1221 * on the parent node. When a hook is created on the cloned 1222 * node it will be removed from this list. When the parent 1223 * is destroyed it will destroy any embryonic children it has. 1224 */ 1225 LIST_INSERT_HEAD(&priv->embryos, priv2, siblings); 1226 1227 SOCKBUF_LOCK(&so->so_rcv); 1228 soupcall_set(so, SO_RCV, ng_ksocket_incoming, node); 1229 SOCKBUF_UNLOCK(&so->so_rcv); 1230 SOCKBUF_LOCK(&so->so_snd); 1231 soupcall_set(so, SO_SND, ng_ksocket_incoming, node); 1232 SOCKBUF_UNLOCK(&so->so_snd); 1233 1234 /* Fill in the response data and send it or return it to the caller */ 1235 resp_data = (struct ng_ksocket_accept *)resp->data; 1236 resp_data->nodeid = NG_NODE_ID(node); 1237 if (sa != NULL) 1238 bcopy(sa, &resp_data->addr, sa->sa_len); 1239 NG_SEND_MSG_ID(error, node, resp, priv->response_addr, 0); 1240 1241 out: 1242 if (sa != NULL) 1243 free(sa, M_SONAME); 1244 1245 return (0); 1246 } 1247 1248 /* 1249 * Parse out either an integer value or an alias. 1250 */ 1251 static int 1252 ng_ksocket_parse(const struct ng_ksocket_alias *aliases, 1253 const char *s, int family) 1254 { 1255 int k, val; 1256 char *eptr; 1257 1258 /* Try aliases */ 1259 for (k = 0; aliases[k].name != NULL; k++) { 1260 if (strcmp(s, aliases[k].name) == 0 1261 && aliases[k].family == family) 1262 return aliases[k].value; 1263 } 1264 1265 /* Try parsing as a number */ 1266 val = (int)strtoul(s, &eptr, 10); 1267 if (val < 0 || *eptr != '\0') 1268 return (-1); 1269 return (val); 1270 }
Cache object: 5ec49ad01e7e62242e52091ee50e9f7f
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