1 /* 2 * Copyright (c) 1982, 1986, 1988, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD: src/sys/netinet/ip_divert.c,v 1.42.2.6 2003/01/23 21:06:45 sam Exp $ 30 */ 31 32 #define _IP_VHL 33 34 #include "opt_inet.h" 35 #include "opt_ipdivert.h" 36 #include "opt_ipsec.h" 37 38 #ifndef INET 39 #error "IPDIVERT requires INET." 40 #endif 41 42 #include <sys/param.h> 43 #include <sys/kernel.h> 44 #include <sys/malloc.h> 45 #include <sys/mbuf.h> 46 #include <sys/socket.h> 47 #include <sys/protosw.h> 48 #include <sys/socketvar.h> 49 #include <sys/socketvar2.h> 50 #include <sys/sysctl.h> 51 #include <sys/systm.h> 52 #include <sys/proc.h> 53 #include <sys/priv.h> 54 #include <sys/in_cksum.h> 55 #include <sys/lock.h> 56 #include <sys/msgport.h> 57 58 #include <net/if.h> 59 #include <net/route.h> 60 61 #include <net/netmsg2.h> 62 #include <net/netisr2.h> 63 #include <sys/thread2.h> 64 #include <sys/mplock2.h> 65 66 #include <netinet/in.h> 67 #include <netinet/in_systm.h> 68 #include <netinet/ip.h> 69 #include <netinet/in_pcb.h> 70 #include <netinet/in_var.h> 71 #include <netinet/ip_var.h> 72 #include <netinet/ip_divert.h> 73 74 /* 75 * Divert sockets 76 */ 77 78 /* 79 * Allocate enough space to hold a full IP packet 80 */ 81 #define DIVSNDQ (65536 + 100) 82 #define DIVRCVQ (65536 + 100) 83 84 #define DIV_IS_OUTPUT(sin) ((sin) == NULL || (sin)->sin_addr.s_addr == 0) 85 86 #define DIV_OUTPUT 0x10000 87 #define DIV_INPUT 0x20000 88 89 /* 90 * Divert sockets work in conjunction with ipfw, see the divert(4) 91 * manpage for features. 92 * Internally, packets selected by ipfw in ip_input() or ip_output(), 93 * and never diverted before, are passed to the input queue of the 94 * divert socket with a given 'divert_port' number (as specified in 95 * the matching ipfw rule), and they are tagged with a 16 bit cookie 96 * (representing the rule number of the matching ipfw rule), which 97 * is passed to process reading from the socket. 98 * 99 * Packets written to the divert socket are again tagged with a cookie 100 * (usually the same as above) and a destination address. 101 * If the destination address is INADDR_ANY then the packet is 102 * treated as outgoing and sent to ip_output(), otherwise it is 103 * treated as incoming and sent to ip_input(). 104 * In both cases, the packet is tagged with the cookie. 105 * 106 * On reinjection, processing in ip_input() and ip_output() 107 * will be exactly the same as for the original packet, except that 108 * ipfw processing will start at the rule number after the one 109 * written in the cookie (so, tagging a packet with a cookie of 0 110 * will cause it to be effectively considered as a standard packet). 111 */ 112 113 /* Internal variables */ 114 static struct inpcbinfo divcbinfo; 115 static struct inpcbportinfo divcbportinfo; 116 117 static u_long div_sendspace = DIVSNDQ; /* XXX sysctl ? */ 118 static u_long div_recvspace = DIVRCVQ; /* XXX sysctl ? */ 119 120 static struct mbuf *ip_divert(struct mbuf *, int, int); 121 122 static struct lwkt_token div_token = LWKT_TOKEN_INITIALIZER(div_token); 123 124 /* 125 * Initialize divert connection block queue. 126 */ 127 void 128 div_init(void) 129 { 130 in_pcbinfo_init(&divcbinfo, 0, FALSE); 131 in_pcbportinfo_init(&divcbportinfo, 1, FALSE, 0); 132 /* 133 * XXX We don't use the hash list for divert IP, but it's easier 134 * to allocate a one entry hash list than it is to check all 135 * over the place for hashbase == NULL. 136 */ 137 divcbinfo.hashbase = hashinit(1, M_PCB, &divcbinfo.hashmask); 138 divcbinfo.portinfo = &divcbportinfo; 139 divcbinfo.wildcardhashbase = hashinit(1, M_PCB, 140 &divcbinfo.wildcardhashmask); 141 divcbinfo.ipi_size = sizeof(struct inpcb); 142 ip_divert_p = ip_divert; 143 } 144 145 /* 146 * IPPROTO_DIVERT is not a real IP protocol; don't allow any packets 147 * with that protocol number to enter the system from the outside. 148 */ 149 int 150 div_input(struct mbuf **mp, int *offp, int proto) 151 { 152 struct mbuf *m = *mp; 153 154 ipstat.ips_noproto++; 155 m_freem(m); 156 return(IPPROTO_DONE); 157 } 158 159 /* 160 * Divert a packet by passing it up to the divert socket at port 'port'. 161 * 162 * Setup generic address and protocol structures for div_input routine, 163 * then pass them along with mbuf chain. 164 */ 165 static void 166 div_packet(struct mbuf *m, int incoming, int port) 167 { 168 struct sockaddr_in divsrc = { sizeof divsrc, AF_INET }; 169 struct inpcb *inp; 170 struct socket *sa; 171 struct m_tag *mtag; 172 struct divert_info *divinfo; 173 u_int16_t nport; 174 175 /* Locate the divert info */ 176 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL); 177 divinfo = m_tag_data(mtag); 178 divsrc.sin_port = divinfo->skipto; 179 180 /* 181 * Record receive interface address, if any. 182 * But only for incoming packets. 183 */ 184 divsrc.sin_addr.s_addr = 0; 185 if (incoming) { 186 struct ifaddr_container *ifac; 187 188 /* Find IP address for receive interface */ 189 TAILQ_FOREACH(ifac, &m->m_pkthdr.rcvif->if_addrheads[mycpuid], 190 ifa_link) { 191 struct ifaddr *ifa = ifac->ifa; 192 193 if (ifa->ifa_addr == NULL) 194 continue; 195 if (ifa->ifa_addr->sa_family != AF_INET) 196 continue; 197 divsrc.sin_addr = 198 ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr; 199 break; 200 } 201 } 202 /* 203 * Record the incoming interface name whenever we have one. 204 */ 205 if (m->m_pkthdr.rcvif) { 206 /* 207 * Hide the actual interface name in there in the 208 * sin_zero array. XXX This needs to be moved to a 209 * different sockaddr type for divert, e.g. 210 * sockaddr_div with multiple fields like 211 * sockaddr_dl. Presently we have only 7 bytes 212 * but that will do for now as most interfaces 213 * are 4 or less + 2 or less bytes for unit. 214 * There is probably a faster way of doing this, 215 * possibly taking it from the sockaddr_dl on the iface. 216 * This solves the problem of a P2P link and a LAN interface 217 * having the same address, which can result in the wrong 218 * interface being assigned to the packet when fed back 219 * into the divert socket. Theoretically if the daemon saves 220 * and re-uses the sockaddr_in as suggested in the man pages, 221 * this iface name will come along for the ride. 222 * (see div_output for the other half of this.) 223 */ 224 ksnprintf(divsrc.sin_zero, sizeof divsrc.sin_zero, "%s", 225 m->m_pkthdr.rcvif->if_xname); 226 } 227 228 /* Put packet on socket queue, if any */ 229 sa = NULL; 230 nport = htons((u_int16_t)port); 231 232 /* 233 * XXX 234 * Following loop to locate the inpcb is MPSAFE since the inpcb 235 * insertion/removal happens on the same CPU (CPU0), however, 236 * saving/testing the socket pointer is not MPSAFE. So we still 237 * need to hold BGL here. 238 */ 239 lwkt_gettoken(&div_token); 240 LIST_FOREACH(inp, &divcbinfo.pcblisthead, inp_list) { 241 if (inp->inp_flags & INP_PLACEMARKER) 242 continue; 243 if (inp->inp_lport == nport) 244 sa = inp->inp_socket; 245 } 246 if (sa) { 247 lwkt_gettoken(&sa->so_rcv.ssb_token); 248 if (ssb_appendaddr(&sa->so_rcv, (struct sockaddr *)&divsrc, m, NULL) == 0) 249 m_freem(m); 250 else 251 sorwakeup(sa); 252 lwkt_reltoken(&sa->so_rcv.ssb_token); 253 } else { 254 m_freem(m); 255 ipstat.ips_noproto++; 256 ipstat.ips_delivered--; 257 } 258 lwkt_reltoken(&div_token); 259 } 260 261 static void 262 div_packet_handler(netmsg_t msg) 263 { 264 struct mbuf *m; 265 int port, incoming = 0; 266 267 m = msg->packet.nm_packet; 268 269 port = msg->lmsg.u.ms_result32 & 0xffff; 270 if (msg->lmsg.u.ms_result32 & DIV_INPUT) 271 incoming = 1; 272 div_packet(m, incoming, port); 273 /* no reply, msg embedded in mbuf */ 274 } 275 276 static void 277 divert_packet(struct mbuf *m, int incoming) 278 { 279 struct m_tag *mtag; 280 struct divert_info *divinfo; 281 int port; 282 283 M_ASSERTPKTHDR(m); 284 285 /* Assure header */ 286 if (m->m_len < sizeof(struct ip) && 287 (m = m_pullup(m, sizeof(struct ip))) == NULL) 288 return; 289 290 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL); 291 KASSERT(mtag != NULL, ("%s no divert tag!", __func__)); 292 divinfo = m_tag_data(mtag); 293 294 port = divinfo->port; 295 KASSERT(port != 0, ("%s: port=0", __func__)); 296 297 if (mycpuid != 0) { 298 struct netmsg_packet *nmp; 299 300 nmp = &m->m_hdr.mh_netmsg; 301 netmsg_init(&nmp->base, NULL, &netisr_apanic_rport, 302 0, div_packet_handler); 303 nmp->nm_packet = m; 304 305 nmp->base.lmsg.u.ms_result32 = port; /* port is 16bits */ 306 if (incoming) 307 nmp->base.lmsg.u.ms_result32 |= DIV_INPUT; 308 else 309 nmp->base.lmsg.u.ms_result32 |= DIV_OUTPUT; 310 311 lwkt_sendmsg(netisr_cpuport(0), &nmp->base.lmsg); 312 } else { 313 div_packet(m, incoming, port); 314 } 315 } 316 317 /* 318 * Deliver packet back into the IP processing machinery. 319 * 320 * If no address specified, or address is 0.0.0.0, send to ip_output(); 321 * otherwise, send to ip_input() and mark as having been received on 322 * the interface with that address. 323 */ 324 static int 325 div_output(struct socket *so, struct mbuf *m, 326 struct sockaddr_in *sin, struct mbuf *control) 327 { 328 int error = 0; 329 struct m_tag *mtag; 330 struct divert_info *divinfo; 331 332 if (control) 333 m_freem(control); /* XXX */ 334 335 /* 336 * Prepare the tag for divert info. Note that a packet 337 * with a 0 tag in mh_data is effectively untagged, 338 * so we could optimize that case. 339 */ 340 mtag = m_tag_get(PACKET_TAG_IPFW_DIVERT, sizeof(*divinfo), MB_DONTWAIT); 341 if (mtag == NULL) { 342 error = ENOBUFS; 343 goto cantsend; 344 } 345 m_tag_prepend(m, mtag); 346 347 /* Loopback avoidance and state recovery */ 348 divinfo = m_tag_data(mtag); 349 if (sin) 350 divinfo->skipto = sin->sin_port; 351 else 352 divinfo->skipto = 0; 353 354 /* Reinject packet into the system as incoming or outgoing */ 355 if (DIV_IS_OUTPUT(sin)) { 356 struct ip *const ip = mtod(m, struct ip *); 357 358 /* Don't allow packet length sizes that will crash */ 359 if ((u_short)ntohs(ip->ip_len) > m->m_pkthdr.len) { 360 error = EINVAL; 361 goto cantsend; 362 } 363 364 /* Convert fields to host order for ip_output() */ 365 ip->ip_len = ntohs(ip->ip_len); 366 ip->ip_off = ntohs(ip->ip_off); 367 368 /* Send packet to output processing */ 369 ipstat.ips_rawout++; /* XXX */ 370 error = ip_output(m, NULL, NULL, 371 (so->so_options & SO_DONTROUTE) | 372 IP_ALLOWBROADCAST | IP_RAWOUTPUT, 373 NULL, NULL); 374 } else { 375 ip_input(m); 376 } 377 return error; 378 379 cantsend: 380 m_freem(m); 381 return error; 382 } 383 384 static void 385 div_attach(netmsg_t msg) 386 { 387 struct socket *so = msg->attach.base.nm_so; 388 int proto = msg->attach.nm_proto; 389 struct pru_attach_info *ai = msg->attach.nm_ai; 390 struct inpcb *inp; 391 int error; 392 393 inp = so->so_pcb; 394 if (inp) 395 panic("div_attach"); 396 error = priv_check_cred(ai->p_ucred, PRIV_ROOT, NULL_CRED_OKAY); 397 if (error) 398 goto out; 399 400 error = soreserve(so, div_sendspace, div_recvspace, ai->sb_rlimit); 401 if (error) 402 goto out; 403 lwkt_gettoken(&div_token); 404 error = in_pcballoc(so, &divcbinfo); 405 if (error) { 406 lwkt_reltoken(&div_token); 407 goto out; 408 } 409 inp = (struct inpcb *)so->so_pcb; 410 inp->inp_ip_p = proto; 411 inp->inp_vflag |= INP_IPV4; 412 inp->inp_flags |= INP_HDRINCL; 413 /* 414 * The socket is always "connected" because 415 * we always know "where" to send the packet. 416 */ 417 sosetstate(so, SS_ISCONNECTED); 418 lwkt_reltoken(&div_token); 419 error = 0; 420 out: 421 lwkt_replymsg(&msg->attach.base.lmsg, error); 422 } 423 424 static void 425 div_detach(netmsg_t msg) 426 { 427 struct socket *so = msg->detach.base.nm_so; 428 struct inpcb *inp; 429 430 inp = so->so_pcb; 431 if (inp == NULL) 432 panic("div_detach"); 433 in_pcbdetach(inp); 434 lwkt_replymsg(&msg->detach.base.lmsg, 0); 435 } 436 437 /* 438 * NOTE: (so) is referenced from soabort*() and netmsg_pru_abort() 439 * will sofree() it when we return. 440 */ 441 static void 442 div_abort(netmsg_t msg) 443 { 444 struct socket *so = msg->abort.base.nm_so; 445 446 soisdisconnected(so); 447 div_detach(msg); 448 /* msg invalid now */ 449 } 450 451 static void 452 div_disconnect(netmsg_t msg) 453 { 454 struct socket *so = msg->disconnect.base.nm_so; 455 int error; 456 457 if (so->so_state & SS_ISCONNECTED) { 458 soreference(so); 459 div_abort(msg); 460 /* msg invalid now */ 461 sofree(so); 462 return; 463 } 464 error = ENOTCONN; 465 lwkt_replymsg(&msg->disconnect.base.lmsg, error); 466 } 467 468 static void 469 div_bind(netmsg_t msg) 470 { 471 struct socket *so = msg->bind.base.nm_so; 472 struct sockaddr *nam = msg->bind.nm_nam; 473 int error; 474 475 /* 476 * in_pcbbind assumes that nam is a sockaddr_in 477 * and in_pcbbind requires a valid address. Since divert 478 * sockets don't we need to make sure the address is 479 * filled in properly. 480 * XXX -- divert should not be abusing in_pcbind 481 * and should probably have its own family. 482 */ 483 if (nam->sa_family != AF_INET) { 484 error = EAFNOSUPPORT; 485 } else { 486 ((struct sockaddr_in *)nam)->sin_addr.s_addr = INADDR_ANY; 487 error = in_pcbbind(so->so_pcb, nam, msg->bind.nm_td); 488 } 489 lwkt_replymsg(&msg->bind.base.lmsg, error); 490 } 491 492 static void 493 div_shutdown(netmsg_t msg) 494 { 495 struct socket *so = msg->shutdown.base.nm_so; 496 497 socantsendmore(so); 498 499 lwkt_replymsg(&msg->shutdown.base.lmsg, 0); 500 } 501 502 static void 503 div_send(netmsg_t msg) 504 { 505 struct socket *so = msg->send.base.nm_so; 506 struct mbuf *m = msg->send.nm_m; 507 struct sockaddr *nam = msg->send.nm_addr; 508 struct mbuf *control = msg->send.nm_control; 509 int error; 510 511 /* Length check already done in ip_hashfn() */ 512 KASSERT(m->m_len >= sizeof(struct ip), ("IP header not in one mbuf")); 513 514 /* Send packet */ 515 error = div_output(so, m, (struct sockaddr_in *)nam, control); 516 lwkt_replymsg(&msg->send.base.lmsg, error); 517 } 518 519 SYSCTL_DECL(_net_inet_divert); 520 SYSCTL_PROC(_net_inet_divert, OID_AUTO, pcblist, CTLFLAG_RD, &divcbinfo, 1, 521 in_pcblist_global, "S,xinpcb", "List of active divert sockets"); 522 523 struct pr_usrreqs div_usrreqs = { 524 .pru_abort = div_abort, 525 .pru_accept = pr_generic_notsupp, 526 .pru_attach = div_attach, 527 .pru_bind = div_bind, 528 .pru_connect = pr_generic_notsupp, 529 .pru_connect2 = pr_generic_notsupp, 530 .pru_control = in_control_dispatch, 531 .pru_detach = div_detach, 532 .pru_disconnect = div_disconnect, 533 .pru_listen = pr_generic_notsupp, 534 .pru_peeraddr = in_setpeeraddr_dispatch, 535 .pru_rcvd = pr_generic_notsupp, 536 .pru_rcvoob = pr_generic_notsupp, 537 .pru_send = div_send, 538 .pru_sense = pru_sense_null, 539 .pru_shutdown = div_shutdown, 540 .pru_sockaddr = in_setsockaddr_dispatch, 541 .pru_sosend = sosend, 542 .pru_soreceive = soreceive 543 }; 544 545 static struct mbuf * 546 ip_divert_out(struct mbuf *m, int tee) 547 { 548 struct mbuf *clone = NULL; 549 struct ip *ip = mtod(m, struct ip *); 550 551 /* Clone packet if we're doing a 'tee' */ 552 if (tee) 553 clone = m_dup(m, MB_DONTWAIT); 554 555 /* 556 * XXX 557 * delayed checksums are not currently compatible 558 * with divert sockets. 559 */ 560 if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { 561 in_delayed_cksum(m); 562 m->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; 563 } 564 565 /* Restore packet header fields to original values */ 566 ip->ip_len = htons(ip->ip_len); 567 ip->ip_off = htons(ip->ip_off); 568 569 /* Deliver packet to divert input routine */ 570 divert_packet(m, 0); 571 572 /* If 'tee', continue with original packet */ 573 return clone; 574 } 575 576 static struct mbuf * 577 ip_divert_in(struct mbuf *m, int tee) 578 { 579 struct mbuf *clone = NULL; 580 struct ip *ip = mtod(m, struct ip *); 581 struct m_tag *mtag; 582 583 if (ip->ip_off & (IP_MF | IP_OFFMASK)) { 584 const struct divert_info *divinfo; 585 u_short frag_off; 586 int hlen; 587 588 /* 589 * Only trust divert info in the fragment 590 * at offset 0. 591 */ 592 frag_off = ip->ip_off << 3; 593 if (frag_off != 0) { 594 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL); 595 m_tag_delete(m, mtag); 596 } 597 598 /* 599 * Attempt reassembly; if it succeeds, proceed. 600 * ip_reass() will return a different mbuf. 601 */ 602 m = ip_reass(m); 603 if (m == NULL) 604 return NULL; 605 ip = mtod(m, struct ip *); 606 607 /* Caller need to redispatch the packet, if it is for us */ 608 m->m_pkthdr.fw_flags |= FW_MBUF_REDISPATCH; 609 610 /* 611 * Get the header length of the reassembled 612 * packet 613 */ 614 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 615 616 /* 617 * Restore original checksum before diverting 618 * packet 619 */ 620 ip->ip_len += hlen; 621 ip->ip_len = htons(ip->ip_len); 622 ip->ip_off = htons(ip->ip_off); 623 ip->ip_sum = 0; 624 if (hlen == sizeof(struct ip)) 625 ip->ip_sum = in_cksum_hdr(ip); 626 else 627 ip->ip_sum = in_cksum(m, hlen); 628 ip->ip_off = ntohs(ip->ip_off); 629 ip->ip_len = ntohs(ip->ip_len); 630 631 /* 632 * Only use the saved divert info 633 */ 634 mtag = m_tag_find(m, PACKET_TAG_IPFW_DIVERT, NULL); 635 if (mtag == NULL) { 636 /* Wrongly configured ipfw */ 637 kprintf("ip_input no divert info\n"); 638 m_freem(m); 639 return NULL; 640 } 641 divinfo = m_tag_data(mtag); 642 tee = divinfo->tee; 643 } 644 645 /* 646 * Divert or tee packet to the divert protocol if 647 * required. 648 */ 649 650 /* Clone packet if we're doing a 'tee' */ 651 if (tee) 652 clone = m_dup(m, MB_DONTWAIT); 653 654 /* 655 * Restore packet header fields to original 656 * values 657 */ 658 ip->ip_len = htons(ip->ip_len); 659 ip->ip_off = htons(ip->ip_off); 660 661 /* Deliver packet to divert input routine */ 662 divert_packet(m, 1); 663 664 /* Catch invalid reference */ 665 m = NULL; 666 ip = NULL; 667 668 ipstat.ips_delivered++; 669 670 /* If 'tee', continue with original packet */ 671 if (clone != NULL) { 672 /* 673 * Complete processing of the packet. 674 * XXX Better safe than sorry, remove the DIVERT tag. 675 */ 676 mtag = m_tag_find(clone, PACKET_TAG_IPFW_DIVERT, NULL); 677 KKASSERT(mtag != NULL); 678 m_tag_delete(clone, mtag); 679 } 680 return clone; 681 } 682 683 static struct mbuf * 684 ip_divert(struct mbuf *m, int tee, int incoming) 685 { 686 struct mbuf *ret; 687 688 if (incoming) 689 ret = ip_divert_in(m, tee); 690 else 691 ret = ip_divert_out(m, tee); 692 return ret; 693 } 694