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1.1.1.5 root 1: /*
2: * libslirp glue
3: *
4: * Copyright (c) 2004-2008 Fabrice Bellard
5: *
6: * Permission is hereby granted, free of charge, to any person obtaining a copy
7: * of this software and associated documentation files (the "Software"), to deal
8: * in the Software without restriction, including without limitation the rights
9: * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10: * copies of the Software, and to permit persons to whom the Software is
11: * furnished to do so, subject to the following conditions:
12: *
13: * The above copyright notice and this permission notice shall be included in
14: * all copies or substantial portions of the Software.
15: *
16: * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17: * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18: * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19: * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20: * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21: * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22: * THE SOFTWARE.
23: */
24: #include "qemu-common.h"
1.1.1.6 ! root 25: #include "qemu-timer.h"
1.1.1.5 root 26: #include "qemu-char.h"
1.1 root 27: #include "slirp.h"
1.1.1.5 root 28: #include "hw/hw.h"
1.1 root 29:
30: /* host address */
31: struct in_addr our_addr;
32: /* host dns address */
33: struct in_addr dns_addr;
34: /* host loopback address */
35: struct in_addr loopback_addr;
36:
1.1.1.6 ! root 37: /* emulated hosts use the MAC addr 52:55:IP:IP:IP:IP */
1.1.1.4 root 38: static const uint8_t special_ethaddr[6] = {
1.1.1.6 ! root 39: 0x52, 0x55, 0x00, 0x00, 0x00, 0x00
1.1 root 40: };
41:
1.1.1.5 root 42: static const uint8_t zero_ethaddr[6] = { 0, 0, 0, 0, 0, 0 };
1.1 root 43:
44: /* XXX: suppress those select globals */
45: fd_set *global_readfds, *global_writefds, *global_xfds;
46:
1.1.1.6 ! root 47: u_int curtime;
! 48: static u_int time_fasttimo, last_slowtimo;
! 49: static int do_slowtimo;
! 50:
! 51: static TAILQ_HEAD(slirp_instances, Slirp) slirp_instances =
! 52: TAILQ_HEAD_INITIALIZER(slirp_instances);
1.1.1.2 root 53:
1.1 root 54: #ifdef _WIN32
55:
56: static int get_dns_addr(struct in_addr *pdns_addr)
57: {
58: FIXED_INFO *FixedInfo=NULL;
59: ULONG BufLen;
60: DWORD ret;
61: IP_ADDR_STRING *pIPAddr;
62: struct in_addr tmp_addr;
1.1.1.4 root 63:
1.1 root 64: FixedInfo = (FIXED_INFO *)GlobalAlloc(GPTR, sizeof(FIXED_INFO));
65: BufLen = sizeof(FIXED_INFO);
1.1.1.4 root 66:
1.1 root 67: if (ERROR_BUFFER_OVERFLOW == GetNetworkParams(FixedInfo, &BufLen)) {
68: if (FixedInfo) {
69: GlobalFree(FixedInfo);
70: FixedInfo = NULL;
71: }
72: FixedInfo = GlobalAlloc(GPTR, BufLen);
73: }
1.1.1.4 root 74:
1.1 root 75: if ((ret = GetNetworkParams(FixedInfo, &BufLen)) != ERROR_SUCCESS) {
76: printf("GetNetworkParams failed. ret = %08x\n", (u_int)ret );
77: if (FixedInfo) {
78: GlobalFree(FixedInfo);
79: FixedInfo = NULL;
80: }
81: return -1;
82: }
1.1.1.4 root 83:
1.1 root 84: pIPAddr = &(FixedInfo->DnsServerList);
85: inet_aton(pIPAddr->IpAddress.String, &tmp_addr);
86: *pdns_addr = tmp_addr;
87: if (FixedInfo) {
88: GlobalFree(FixedInfo);
89: FixedInfo = NULL;
90: }
91: return 0;
92: }
93:
1.1.1.6 ! root 94: static void winsock_cleanup(void)
! 95: {
! 96: WSACleanup();
! 97: }
! 98:
1.1 root 99: #else
100:
101: static int get_dns_addr(struct in_addr *pdns_addr)
102: {
103: char buff[512];
1.1.1.5 root 104: char buff2[257];
1.1 root 105: FILE *f;
106: int found = 0;
107: struct in_addr tmp_addr;
1.1.1.4 root 108:
1.1 root 109: f = fopen("/etc/resolv.conf", "r");
110: if (!f)
111: return -1;
112:
1.1.1.4 root 113: #ifdef DEBUG
1.1 root 114: lprint("IP address of your DNS(s): ");
1.1.1.4 root 115: #endif
1.1 root 116: while (fgets(buff, 512, f) != NULL) {
117: if (sscanf(buff, "nameserver%*[ \t]%256s", buff2) == 1) {
118: if (!inet_aton(buff2, &tmp_addr))
119: continue;
120: if (tmp_addr.s_addr == loopback_addr.s_addr)
121: tmp_addr = our_addr;
122: /* If it's the first one, set it to dns_addr */
123: if (!found)
124: *pdns_addr = tmp_addr;
1.1.1.4 root 125: #ifdef DEBUG
1.1 root 126: else
127: lprint(", ");
1.1.1.4 root 128: #endif
1.1 root 129: if (++found > 3) {
1.1.1.4 root 130: #ifdef DEBUG
1.1 root 131: lprint("(more)");
1.1.1.4 root 132: #endif
1.1 root 133: break;
1.1.1.4 root 134: }
135: #ifdef DEBUG
136: else
1.1 root 137: lprint("%s", inet_ntoa(tmp_addr));
1.1.1.4 root 138: #endif
1.1 root 139: }
140: }
141: fclose(f);
142: if (!found)
143: return -1;
144: return 0;
145: }
146:
147: #endif
148:
1.1.1.6 ! root 149: static void slirp_init_once(void)
1.1 root 150: {
1.1.1.6 ! root 151: static int initialized;
! 152: struct hostent *he;
! 153: char our_name[256];
! 154: #ifdef _WIN32
! 155: WSADATA Data;
1.1 root 156: #endif
157:
1.1.1.6 ! root 158: if (initialized) {
! 159: return;
! 160: }
! 161: initialized = 1;
! 162:
! 163: #ifdef _WIN32
! 164: WSAStartup(MAKEWORD(2,0), &Data);
! 165: atexit(winsock_cleanup);
! 166: #endif
! 167:
! 168: loopback_addr.s_addr = htonl(INADDR_LOOPBACK);
! 169:
! 170: /* FIXME: This address may change during runtime */
! 171: if (gethostname(our_name, sizeof(our_name)) == 0) {
! 172: he = gethostbyname(our_name);
! 173: if (he) {
! 174: our_addr = *(struct in_addr *)he->h_addr;
! 175: }
! 176: }
! 177: if (our_addr.s_addr == 0) {
! 178: our_addr = loopback_addr;
! 179: }
! 180:
! 181: /* FIXME: This address may change during runtime */
! 182: if (get_dns_addr(&dns_addr) < 0) {
! 183: dns_addr = loopback_addr;
! 184: }
! 185: }
! 186:
1.1.1.5 root 187: static void slirp_state_save(QEMUFile *f, void *opaque);
188: static int slirp_state_load(QEMUFile *f, void *opaque, int version_id);
189:
1.1.1.6 ! root 190: Slirp *slirp_init(int restricted, struct in_addr vnetwork,
! 191: struct in_addr vnetmask, struct in_addr vhost,
! 192: const char *vhostname, const char *tftp_path,
! 193: const char *bootfile, struct in_addr vdhcp_start,
! 194: struct in_addr vnameserver, void *opaque)
1.1 root 195: {
1.1.1.6 ! root 196: Slirp *slirp = qemu_mallocz(sizeof(Slirp));
1.1.1.4 root 197:
1.1.1.6 ! root 198: slirp_init_once();
1.1 root 199:
1.1.1.6 ! root 200: slirp->restricted = restricted;
1.1 root 201:
1.1.1.6 ! root 202: if_init(slirp);
! 203: ip_init(slirp);
1.1 root 204:
205: /* Initialise mbufs *after* setting the MTU */
1.1.1.6 ! root 206: m_init(slirp);
1.1 root 207:
1.1.1.6 ! root 208: slirp->vnetwork_addr = vnetwork;
! 209: slirp->vnetwork_mask = vnetmask;
! 210: slirp->vhost_addr = vhost;
! 211: if (vhostname) {
! 212: pstrcpy(slirp->client_hostname, sizeof(slirp->client_hostname),
! 213: vhostname);
! 214: }
! 215: if (tftp_path) {
! 216: slirp->tftp_prefix = qemu_strdup(tftp_path);
1.1 root 217: }
1.1.1.6 ! root 218: if (bootfile) {
! 219: slirp->bootp_filename = qemu_strdup(bootfile);
! 220: }
! 221: slirp->vdhcp_startaddr = vdhcp_start;
! 222: slirp->vnameserver_addr = vnameserver;
1.1 root 223:
1.1.1.6 ! root 224: slirp->opaque = opaque;
1.1.1.5 root 225:
1.1.1.6 ! root 226: register_savevm("slirp", 0, 3, slirp_state_save, slirp_state_load, slirp);
1.1 root 227:
1.1.1.6 ! root 228: TAILQ_INSERT_TAIL(&slirp_instances, slirp, entry);
1.1 root 229:
1.1.1.6 ! root 230: return slirp;
1.1 root 231: }
1.1.1.6 ! root 232:
! 233: void slirp_cleanup(Slirp *slirp)
1.1 root 234: {
1.1.1.6 ! root 235: TAILQ_REMOVE(&slirp_instances, slirp, entry);
1.1.1.4 root 236:
1.1.1.6 ! root 237: unregister_savevm("slirp", slirp);
1.1.1.4 root 238:
1.1.1.6 ! root 239: qemu_free(slirp->tftp_prefix);
! 240: qemu_free(slirp->bootp_filename);
! 241: qemu_free(slirp);
1.1 root 242: }
1.1.1.6 ! root 243:
! 244: #define CONN_CANFSEND(so) (((so)->so_state & (SS_FCANTSENDMORE|SS_ISFCONNECTED)) == SS_ISFCONNECTED)
! 245: #define CONN_CANFRCV(so) (((so)->so_state & (SS_FCANTRCVMORE|SS_ISFCONNECTED)) == SS_ISFCONNECTED)
! 246: #define UPD_NFDS(x) if (nfds < (x)) nfds = (x)
1.1 root 247:
1.1.1.4 root 248: void slirp_select_fill(int *pnfds,
1.1 root 249: fd_set *readfds, fd_set *writefds, fd_set *xfds)
250: {
1.1.1.6 ! root 251: Slirp *slirp;
1.1 root 252: struct socket *so, *so_next;
253: int nfds;
1.1.1.6 ! root 254:
! 255: if (TAILQ_EMPTY(&slirp_instances)) {
! 256: return;
! 257: }
1.1 root 258:
259: /* fail safe */
260: global_readfds = NULL;
261: global_writefds = NULL;
262: global_xfds = NULL;
1.1.1.4 root 263:
1.1 root 264: nfds = *pnfds;
265: /*
266: * First, TCP sockets
267: */
268: do_slowtimo = 0;
1.1.1.6 ! root 269:
! 270: TAILQ_FOREACH(slirp, &slirp_instances, entry) {
1.1.1.4 root 271: /*
1.1 root 272: * *_slowtimo needs calling if there are IP fragments
273: * in the fragment queue, or there are TCP connections active
274: */
1.1.1.6 ! root 275: do_slowtimo |= ((slirp->tcb.so_next != &slirp->tcb) ||
! 276: (&slirp->ipq.ip_link != slirp->ipq.ip_link.next));
1.1.1.4 root 277:
1.1.1.6 ! root 278: for (so = slirp->tcb.so_next; so != &slirp->tcb;
! 279: so = so_next) {
1.1 root 280: so_next = so->so_next;
1.1.1.4 root 281:
1.1 root 282: /*
283: * See if we need a tcp_fasttimo
284: */
285: if (time_fasttimo == 0 && so->so_tcpcb->t_flags & TF_DELACK)
286: time_fasttimo = curtime; /* Flag when we want a fasttimo */
1.1.1.4 root 287:
1.1 root 288: /*
289: * NOFDREF can include still connecting to local-host,
290: * newly socreated() sockets etc. Don't want to select these.
291: */
292: if (so->so_state & SS_NOFDREF || so->s == -1)
293: continue;
1.1.1.4 root 294:
1.1 root 295: /*
296: * Set for reading sockets which are accepting
297: */
298: if (so->so_state & SS_FACCEPTCONN) {
299: FD_SET(so->s, readfds);
300: UPD_NFDS(so->s);
301: continue;
302: }
1.1.1.4 root 303:
1.1 root 304: /*
305: * Set for writing sockets which are connecting
306: */
307: if (so->so_state & SS_ISFCONNECTING) {
308: FD_SET(so->s, writefds);
309: UPD_NFDS(so->s);
310: continue;
311: }
1.1.1.4 root 312:
1.1 root 313: /*
314: * Set for writing if we are connected, can send more, and
315: * we have something to send
316: */
317: if (CONN_CANFSEND(so) && so->so_rcv.sb_cc) {
318: FD_SET(so->s, writefds);
319: UPD_NFDS(so->s);
320: }
1.1.1.4 root 321:
1.1 root 322: /*
323: * Set for reading (and urgent data) if we are connected, can
324: * receive more, and we have room for it XXX /2 ?
325: */
326: if (CONN_CANFRCV(so) && (so->so_snd.sb_cc < (so->so_snd.sb_datalen/2))) {
327: FD_SET(so->s, readfds);
328: FD_SET(so->s, xfds);
329: UPD_NFDS(so->s);
330: }
331: }
1.1.1.4 root 332:
1.1 root 333: /*
334: * UDP sockets
335: */
1.1.1.6 ! root 336: for (so = slirp->udb.so_next; so != &slirp->udb;
! 337: so = so_next) {
1.1 root 338: so_next = so->so_next;
1.1.1.4 root 339:
1.1 root 340: /*
341: * See if it's timed out
342: */
343: if (so->so_expire) {
344: if (so->so_expire <= curtime) {
345: udp_detach(so);
346: continue;
347: } else
348: do_slowtimo = 1; /* Let socket expire */
349: }
1.1.1.4 root 350:
1.1 root 351: /*
352: * When UDP packets are received from over the
353: * link, they're sendto()'d straight away, so
354: * no need for setting for writing
355: * Limit the number of packets queued by this session
356: * to 4. Note that even though we try and limit this
357: * to 4 packets, the session could have more queued
358: * if the packets needed to be fragmented
359: * (XXX <= 4 ?)
360: */
361: if ((so->so_state & SS_ISFCONNECTED) && so->so_queued <= 4) {
362: FD_SET(so->s, readfds);
363: UPD_NFDS(so->s);
364: }
365: }
366: }
1.1.1.4 root 367:
1.1 root 368: *pnfds = nfds;
1.1.1.4 root 369: }
1.1 root 370:
1.1.1.6 ! root 371: void slirp_select_poll(fd_set *readfds, fd_set *writefds, fd_set *xfds,
! 372: int select_error)
1.1 root 373: {
1.1.1.6 ! root 374: Slirp *slirp;
1.1 root 375: struct socket *so, *so_next;
376: int ret;
377:
1.1.1.6 ! root 378: if (TAILQ_EMPTY(&slirp_instances)) {
! 379: return;
! 380: }
! 381:
1.1 root 382: global_readfds = readfds;
383: global_writefds = writefds;
384: global_xfds = xfds;
385:
1.1.1.6 ! root 386: curtime = qemu_get_clock(rt_clock);
1.1.1.4 root 387:
1.1.1.6 ! root 388: TAILQ_FOREACH(slirp, &slirp_instances, entry) {
1.1 root 389: /*
1.1.1.4 root 390: * See if anything has timed out
1.1 root 391: */
392: if (time_fasttimo && ((curtime - time_fasttimo) >= 2)) {
1.1.1.6 ! root 393: tcp_fasttimo(slirp);
1.1 root 394: time_fasttimo = 0;
395: }
396: if (do_slowtimo && ((curtime - last_slowtimo) >= 499)) {
1.1.1.6 ! root 397: ip_slowtimo(slirp);
! 398: tcp_slowtimo(slirp);
1.1 root 399: last_slowtimo = curtime;
400: }
1.1.1.4 root 401:
1.1 root 402: /*
403: * Check sockets
404: */
1.1.1.6 ! root 405: if (!select_error) {
1.1 root 406: /*
407: * Check TCP sockets
408: */
1.1.1.6 ! root 409: for (so = slirp->tcb.so_next; so != &slirp->tcb;
! 410: so = so_next) {
1.1 root 411: so_next = so->so_next;
1.1.1.4 root 412:
1.1 root 413: /*
414: * FD_ISSET is meaningless on these sockets
415: * (and they can crash the program)
416: */
417: if (so->so_state & SS_NOFDREF || so->s == -1)
418: continue;
1.1.1.4 root 419:
1.1 root 420: /*
421: * Check for URG data
422: * This will soread as well, so no need to
423: * test for readfds below if this succeeds
424: */
425: if (FD_ISSET(so->s, xfds))
426: sorecvoob(so);
427: /*
428: * Check sockets for reading
429: */
430: else if (FD_ISSET(so->s, readfds)) {
431: /*
432: * Check for incoming connections
433: */
434: if (so->so_state & SS_FACCEPTCONN) {
435: tcp_connect(so);
436: continue;
437: } /* else */
438: ret = soread(so);
1.1.1.4 root 439:
1.1 root 440: /* Output it if we read something */
441: if (ret > 0)
442: tcp_output(sototcpcb(so));
443: }
1.1.1.4 root 444:
1.1 root 445: /*
446: * Check sockets for writing
447: */
448: if (FD_ISSET(so->s, writefds)) {
449: /*
450: * Check for non-blocking, still-connecting sockets
451: */
452: if (so->so_state & SS_ISFCONNECTING) {
453: /* Connected */
454: so->so_state &= ~SS_ISFCONNECTING;
1.1.1.4 root 455:
1.1.1.6 ! root 456: ret = send(so->s, (const void *) &ret, 0, 0);
1.1 root 457: if (ret < 0) {
458: /* XXXXX Must fix, zero bytes is a NOP */
459: if (errno == EAGAIN || errno == EWOULDBLOCK ||
460: errno == EINPROGRESS || errno == ENOTCONN)
461: continue;
1.1.1.4 root 462:
1.1 root 463: /* else failed */
1.1.1.6 ! root 464: so->so_state &= SS_PERSISTENT_MASK;
! 465: so->so_state |= SS_NOFDREF;
1.1 root 466: }
467: /* else so->so_state &= ~SS_ISFCONNECTING; */
1.1.1.4 root 468:
1.1 root 469: /*
470: * Continue tcp_input
471: */
472: tcp_input((struct mbuf *)NULL, sizeof(struct ip), so);
473: /* continue; */
474: } else
475: ret = sowrite(so);
476: /*
1.1.1.4 root 477: * XXXXX If we wrote something (a lot), there
1.1 root 478: * could be a need for a window update.
479: * In the worst case, the remote will send
480: * a window probe to get things going again
481: */
482: }
1.1.1.4 root 483:
1.1 root 484: /*
485: * Probe a still-connecting, non-blocking socket
486: * to check if it's still alive
487: */
488: #ifdef PROBE_CONN
489: if (so->so_state & SS_ISFCONNECTING) {
490: ret = recv(so->s, (char *)&ret, 0,0);
1.1.1.4 root 491:
1.1 root 492: if (ret < 0) {
493: /* XXX */
494: if (errno == EAGAIN || errno == EWOULDBLOCK ||
495: errno == EINPROGRESS || errno == ENOTCONN)
496: continue; /* Still connecting, continue */
1.1.1.4 root 497:
1.1 root 498: /* else failed */
1.1.1.6 ! root 499: so->so_state &= SS_PERSISTENT_MASK;
! 500: so->so_state |= SS_NOFDREF;
1.1.1.4 root 501:
1.1 root 502: /* tcp_input will take care of it */
503: } else {
504: ret = send(so->s, &ret, 0,0);
505: if (ret < 0) {
506: /* XXX */
507: if (errno == EAGAIN || errno == EWOULDBLOCK ||
508: errno == EINPROGRESS || errno == ENOTCONN)
509: continue;
510: /* else failed */
1.1.1.6 ! root 511: so->so_state &= SS_PERSISTENT_MASK;
! 512: so->so_state |= SS_NOFDREF;
1.1 root 513: } else
514: so->so_state &= ~SS_ISFCONNECTING;
1.1.1.4 root 515:
1.1 root 516: }
517: tcp_input((struct mbuf *)NULL, sizeof(struct ip),so);
518: } /* SS_ISFCONNECTING */
519: #endif
520: }
1.1.1.4 root 521:
1.1 root 522: /*
523: * Now UDP sockets.
524: * Incoming packets are sent straight away, they're not buffered.
525: * Incoming UDP data isn't buffered either.
526: */
1.1.1.6 ! root 527: for (so = slirp->udb.so_next; so != &slirp->udb;
! 528: so = so_next) {
1.1 root 529: so_next = so->so_next;
1.1.1.4 root 530:
1.1 root 531: if (so->s != -1 && FD_ISSET(so->s, readfds)) {
532: sorecvfrom(so);
533: }
534: }
535: }
1.1.1.4 root 536:
1.1 root 537: /*
538: * See if we can start outputting
539: */
1.1.1.6 ! root 540: if (slirp->if_queued) {
! 541: if_start(slirp);
! 542: }
! 543: }
1.1 root 544:
545: /* clear global file descriptor sets.
546: * these reside on the stack in vl.c
547: * so they're unusable if we're not in
548: * slirp_select_fill or slirp_select_poll.
549: */
550: global_readfds = NULL;
551: global_writefds = NULL;
552: global_xfds = NULL;
553: }
554:
555: #define ETH_ALEN 6
556: #define ETH_HLEN 14
557:
558: #define ETH_P_IP 0x0800 /* Internet Protocol packet */
559: #define ETH_P_ARP 0x0806 /* Address Resolution packet */
560:
561: #define ARPOP_REQUEST 1 /* ARP request */
562: #define ARPOP_REPLY 2 /* ARP reply */
563:
1.1.1.4 root 564: struct ethhdr
1.1 root 565: {
566: unsigned char h_dest[ETH_ALEN]; /* destination eth addr */
567: unsigned char h_source[ETH_ALEN]; /* source ether addr */
568: unsigned short h_proto; /* packet type ID field */
569: };
570:
571: struct arphdr
572: {
573: unsigned short ar_hrd; /* format of hardware address */
574: unsigned short ar_pro; /* format of protocol address */
575: unsigned char ar_hln; /* length of hardware address */
576: unsigned char ar_pln; /* length of protocol address */
577: unsigned short ar_op; /* ARP opcode (command) */
578:
579: /*
580: * Ethernet looks like this : This bit is variable sized however...
581: */
582: unsigned char ar_sha[ETH_ALEN]; /* sender hardware address */
1.1.1.6 ! root 583: uint32_t ar_sip; /* sender IP address */
1.1 root 584: unsigned char ar_tha[ETH_ALEN]; /* target hardware address */
1.1.1.6 ! root 585: uint32_t ar_tip ; /* target IP address */
! 586: } __attribute__((packed));
1.1 root 587:
1.1.1.6 ! root 588: static void arp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len)
1.1 root 589: {
590: struct ethhdr *eh = (struct ethhdr *)pkt;
591: struct arphdr *ah = (struct arphdr *)(pkt + ETH_HLEN);
592: uint8_t arp_reply[ETH_HLEN + sizeof(struct arphdr)];
593: struct ethhdr *reh = (struct ethhdr *)arp_reply;
594: struct arphdr *rah = (struct arphdr *)(arp_reply + ETH_HLEN);
595: int ar_op;
596: struct ex_list *ex_ptr;
597:
598: ar_op = ntohs(ah->ar_op);
599: switch(ar_op) {
600: case ARPOP_REQUEST:
1.1.1.6 ! root 601: if ((ah->ar_tip & slirp->vnetwork_mask.s_addr) ==
! 602: slirp->vnetwork_addr.s_addr) {
! 603: if (ah->ar_tip == slirp->vnameserver_addr.s_addr ||
! 604: ah->ar_tip == slirp->vhost_addr.s_addr)
1.1 root 605: goto arp_ok;
1.1.1.6 ! root 606: for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) {
! 607: if (ex_ptr->ex_addr.s_addr == ah->ar_tip)
1.1 root 608: goto arp_ok;
609: }
610: return;
611: arp_ok:
612: /* XXX: make an ARP request to have the client address */
1.1.1.6 ! root 613: memcpy(slirp->client_ethaddr, eh->h_source, ETH_ALEN);
1.1 root 614:
615: /* ARP request for alias/dns mac address */
616: memcpy(reh->h_dest, pkt + ETH_ALEN, ETH_ALEN);
1.1.1.6 ! root 617: memcpy(reh->h_source, special_ethaddr, ETH_ALEN - 4);
! 618: memcpy(&reh->h_source[2], &ah->ar_tip, 4);
1.1 root 619: reh->h_proto = htons(ETH_P_ARP);
620:
621: rah->ar_hrd = htons(1);
622: rah->ar_pro = htons(ETH_P_IP);
623: rah->ar_hln = ETH_ALEN;
624: rah->ar_pln = 4;
625: rah->ar_op = htons(ARPOP_REPLY);
626: memcpy(rah->ar_sha, reh->h_source, ETH_ALEN);
1.1.1.6 ! root 627: rah->ar_sip = ah->ar_tip;
1.1 root 628: memcpy(rah->ar_tha, ah->ar_sha, ETH_ALEN);
1.1.1.6 ! root 629: rah->ar_tip = ah->ar_sip;
! 630: slirp_output(slirp->opaque, arp_reply, sizeof(arp_reply));
1.1 root 631: }
632: break;
1.1.1.5 root 633: case ARPOP_REPLY:
634: /* reply to request of client mac address ? */
1.1.1.6 ! root 635: if (!memcmp(slirp->client_ethaddr, zero_ethaddr, ETH_ALEN) &&
! 636: ah->ar_sip == slirp->client_ipaddr.s_addr) {
! 637: memcpy(slirp->client_ethaddr, ah->ar_sha, ETH_ALEN);
1.1.1.5 root 638: }
639: break;
1.1 root 640: default:
641: break;
642: }
643: }
644:
1.1.1.6 ! root 645: void slirp_input(Slirp *slirp, const uint8_t *pkt, int pkt_len)
1.1 root 646: {
647: struct mbuf *m;
648: int proto;
649:
650: if (pkt_len < ETH_HLEN)
651: return;
1.1.1.4 root 652:
1.1 root 653: proto = ntohs(*(uint16_t *)(pkt + 12));
654: switch(proto) {
655: case ETH_P_ARP:
1.1.1.6 ! root 656: arp_input(slirp, pkt, pkt_len);
1.1 root 657: break;
658: case ETH_P_IP:
1.1.1.6 ! root 659: m = m_get(slirp);
1.1 root 660: if (!m)
661: return;
1.1.1.3 root 662: /* Note: we add to align the IP header */
1.1.1.5 root 663: if (M_FREEROOM(m) < pkt_len + 2) {
664: m_inc(m, pkt_len + 2);
665: }
1.1.1.3 root 666: m->m_len = pkt_len + 2;
667: memcpy(m->m_data + 2, pkt, pkt_len);
1.1 root 668:
1.1.1.3 root 669: m->m_data += 2 + ETH_HLEN;
670: m->m_len -= 2 + ETH_HLEN;
1.1 root 671:
672: ip_input(m);
673: break;
674: default:
675: break;
676: }
677: }
678:
679: /* output the IP packet to the ethernet device */
1.1.1.6 ! root 680: void if_encap(Slirp *slirp, const uint8_t *ip_data, int ip_data_len)
1.1 root 681: {
682: uint8_t buf[1600];
683: struct ethhdr *eh = (struct ethhdr *)buf;
684:
685: if (ip_data_len + ETH_HLEN > sizeof(buf))
686: return;
1.1.1.5 root 687:
1.1.1.6 ! root 688: if (!memcmp(slirp->client_ethaddr, zero_ethaddr, ETH_ALEN)) {
1.1.1.5 root 689: uint8_t arp_req[ETH_HLEN + sizeof(struct arphdr)];
690: struct ethhdr *reh = (struct ethhdr *)arp_req;
691: struct arphdr *rah = (struct arphdr *)(arp_req + ETH_HLEN);
692: const struct ip *iph = (const struct ip *)ip_data;
693:
694: /* If the client addr is not known, there is no point in
695: sending the packet to it. Normally the sender should have
696: done an ARP request to get its MAC address. Here we do it
697: in place of sending the packet and we hope that the sender
698: will retry sending its packet. */
699: memset(reh->h_dest, 0xff, ETH_ALEN);
1.1.1.6 ! root 700: memcpy(reh->h_source, special_ethaddr, ETH_ALEN - 4);
! 701: memcpy(&reh->h_source[2], &slirp->vhost_addr, 4);
1.1.1.5 root 702: reh->h_proto = htons(ETH_P_ARP);
703: rah->ar_hrd = htons(1);
704: rah->ar_pro = htons(ETH_P_IP);
705: rah->ar_hln = ETH_ALEN;
706: rah->ar_pln = 4;
707: rah->ar_op = htons(ARPOP_REQUEST);
708: /* source hw addr */
1.1.1.6 ! root 709: memcpy(rah->ar_sha, special_ethaddr, ETH_ALEN - 4);
! 710: memcpy(&rah->ar_sha[2], &slirp->vhost_addr, 4);
1.1.1.5 root 711: /* source IP */
1.1.1.6 ! root 712: rah->ar_sip = slirp->vhost_addr.s_addr;
1.1.1.5 root 713: /* target hw addr (none) */
714: memset(rah->ar_tha, 0, ETH_ALEN);
715: /* target IP */
1.1.1.6 ! root 716: rah->ar_tip = iph->ip_dst.s_addr;
! 717: slirp->client_ipaddr = iph->ip_dst;
! 718: slirp_output(slirp->opaque, arp_req, sizeof(arp_req));
1.1.1.5 root 719: } else {
1.1.1.6 ! root 720: memcpy(eh->h_dest, slirp->client_ethaddr, ETH_ALEN);
! 721: memcpy(eh->h_source, special_ethaddr, ETH_ALEN - 4);
1.1.1.5 root 722: /* XXX: not correct */
1.1.1.6 ! root 723: memcpy(&eh->h_source[2], &slirp->vhost_addr, 4);
1.1.1.5 root 724: eh->h_proto = htons(ETH_P_IP);
725: memcpy(buf + sizeof(struct ethhdr), ip_data, ip_data_len);
1.1.1.6 ! root 726: slirp_output(slirp->opaque, buf, ip_data_len + ETH_HLEN);
1.1.1.5 root 727: }
1.1 root 728: }
729:
1.1.1.6 ! root 730: /* Drop host forwarding rule, return 0 if found. */
! 731: int slirp_remove_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr,
! 732: int host_port)
! 733: {
! 734: struct socket *so;
! 735: struct socket *head = (is_udp ? &slirp->udb : &slirp->tcb);
! 736: struct sockaddr_in addr;
! 737: int port = htons(host_port);
! 738: socklen_t addr_len;
! 739:
! 740: for (so = head->so_next; so != head; so = so->so_next) {
! 741: addr_len = sizeof(addr);
! 742: if ((so->so_state & SS_HOSTFWD) &&
! 743: getsockname(so->s, (struct sockaddr *)&addr, &addr_len) == 0 &&
! 744: addr.sin_addr.s_addr == host_addr.s_addr &&
! 745: addr.sin_port == port) {
! 746: close(so->s);
! 747: sofree(so);
! 748: return 0;
! 749: }
! 750: }
! 751:
! 752: return -1;
! 753: }
! 754:
! 755: int slirp_add_hostfwd(Slirp *slirp, int is_udp, struct in_addr host_addr,
! 756: int host_port, struct in_addr guest_addr, int guest_port)
1.1 root 757: {
1.1.1.6 ! root 758: if (!guest_addr.s_addr) {
! 759: guest_addr = slirp->vdhcp_startaddr;
! 760: }
1.1 root 761: if (is_udp) {
1.1.1.6 ! root 762: if (!udp_listen(slirp, host_addr.s_addr, htons(host_port),
! 763: guest_addr.s_addr, htons(guest_port), SS_HOSTFWD))
1.1 root 764: return -1;
765: } else {
1.1.1.6 ! root 766: if (!tcp_listen(slirp, host_addr.s_addr, htons(host_port),
! 767: guest_addr.s_addr, htons(guest_port), SS_HOSTFWD))
1.1 root 768: return -1;
769: }
770: return 0;
771: }
772:
1.1.1.6 ! root 773: int slirp_add_exec(Slirp *slirp, int do_pty, const void *args,
! 774: struct in_addr *guest_addr, int guest_port)
1.1 root 775: {
1.1.1.6 ! root 776: if (!guest_addr->s_addr) {
! 777: guest_addr->s_addr = slirp->vnetwork_addr.s_addr |
! 778: (htonl(0x0204) & ~slirp->vnetwork_mask.s_addr);
! 779: }
! 780: if ((guest_addr->s_addr & slirp->vnetwork_mask.s_addr) !=
! 781: slirp->vnetwork_addr.s_addr ||
! 782: guest_addr->s_addr == slirp->vhost_addr.s_addr ||
! 783: guest_addr->s_addr == slirp->vnameserver_addr.s_addr) {
! 784: return -1;
! 785: }
! 786: return add_exec(&slirp->exec_list, do_pty, (char *)args, *guest_addr,
! 787: htons(guest_port));
1.1 root 788: }
1.1.1.5 root 789:
790: ssize_t slirp_send(struct socket *so, const void *buf, size_t len, int flags)
791: {
792: if (so->s == -1 && so->extra) {
793: qemu_chr_write(so->extra, buf, len);
794: return len;
795: }
796:
797: return send(so->s, buf, len, flags);
798: }
799:
1.1.1.6 ! root 800: static struct socket *
! 801: slirp_find_ctl_socket(Slirp *slirp, struct in_addr guest_addr, int guest_port)
1.1.1.5 root 802: {
1.1.1.6 ! root 803: struct socket *so;
1.1.1.5 root 804:
1.1.1.6 ! root 805: for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so->so_next) {
! 806: if (so->so_faddr.s_addr == guest_addr.s_addr &&
! 807: htons(so->so_fport) == guest_port) {
! 808: return so;
! 809: }
! 810: }
! 811: return NULL;
1.1.1.5 root 812: }
813:
1.1.1.6 ! root 814: size_t slirp_socket_can_recv(Slirp *slirp, struct in_addr guest_addr,
! 815: int guest_port)
1.1.1.5 root 816: {
817: struct iovec iov[2];
818: struct socket *so;
819:
1.1.1.6 ! root 820: so = slirp_find_ctl_socket(slirp, guest_addr, guest_port);
1.1.1.5 root 821:
822: if (!so || so->so_state & SS_NOFDREF)
823: return 0;
824:
825: if (!CONN_CANFRCV(so) || so->so_snd.sb_cc >= (so->so_snd.sb_datalen/2))
826: return 0;
827:
828: return sopreprbuf(so, iov, NULL);
829: }
830:
1.1.1.6 ! root 831: void slirp_socket_recv(Slirp *slirp, struct in_addr guest_addr, int guest_port,
! 832: const uint8_t *buf, int size)
1.1.1.5 root 833: {
834: int ret;
1.1.1.6 ! root 835: struct socket *so = slirp_find_ctl_socket(slirp, guest_addr, guest_port);
! 836:
1.1.1.5 root 837: if (!so)
838: return;
839:
840: ret = soreadbuf(so, (const char *)buf, size);
841:
842: if (ret > 0)
843: tcp_output(sototcpcb(so));
844: }
845:
846: static void slirp_tcp_save(QEMUFile *f, struct tcpcb *tp)
847: {
848: int i;
849:
850: qemu_put_sbe16(f, tp->t_state);
851: for (i = 0; i < TCPT_NTIMERS; i++)
852: qemu_put_sbe16(f, tp->t_timer[i]);
853: qemu_put_sbe16(f, tp->t_rxtshift);
854: qemu_put_sbe16(f, tp->t_rxtcur);
855: qemu_put_sbe16(f, tp->t_dupacks);
856: qemu_put_be16(f, tp->t_maxseg);
857: qemu_put_sbyte(f, tp->t_force);
858: qemu_put_be16(f, tp->t_flags);
859: qemu_put_be32(f, tp->snd_una);
860: qemu_put_be32(f, tp->snd_nxt);
861: qemu_put_be32(f, tp->snd_up);
862: qemu_put_be32(f, tp->snd_wl1);
863: qemu_put_be32(f, tp->snd_wl2);
864: qemu_put_be32(f, tp->iss);
865: qemu_put_be32(f, tp->snd_wnd);
866: qemu_put_be32(f, tp->rcv_wnd);
867: qemu_put_be32(f, tp->rcv_nxt);
868: qemu_put_be32(f, tp->rcv_up);
869: qemu_put_be32(f, tp->irs);
870: qemu_put_be32(f, tp->rcv_adv);
871: qemu_put_be32(f, tp->snd_max);
872: qemu_put_be32(f, tp->snd_cwnd);
873: qemu_put_be32(f, tp->snd_ssthresh);
874: qemu_put_sbe16(f, tp->t_idle);
875: qemu_put_sbe16(f, tp->t_rtt);
876: qemu_put_be32(f, tp->t_rtseq);
877: qemu_put_sbe16(f, tp->t_srtt);
878: qemu_put_sbe16(f, tp->t_rttvar);
879: qemu_put_be16(f, tp->t_rttmin);
880: qemu_put_be32(f, tp->max_sndwnd);
881: qemu_put_byte(f, tp->t_oobflags);
882: qemu_put_byte(f, tp->t_iobc);
883: qemu_put_sbe16(f, tp->t_softerror);
884: qemu_put_byte(f, tp->snd_scale);
885: qemu_put_byte(f, tp->rcv_scale);
886: qemu_put_byte(f, tp->request_r_scale);
887: qemu_put_byte(f, tp->requested_s_scale);
888: qemu_put_be32(f, tp->ts_recent);
889: qemu_put_be32(f, tp->ts_recent_age);
890: qemu_put_be32(f, tp->last_ack_sent);
891: }
892:
893: static void slirp_sbuf_save(QEMUFile *f, struct sbuf *sbuf)
894: {
895: uint32_t off;
896:
897: qemu_put_be32(f, sbuf->sb_cc);
898: qemu_put_be32(f, sbuf->sb_datalen);
899: off = (uint32_t)(sbuf->sb_wptr - sbuf->sb_data);
900: qemu_put_sbe32(f, off);
901: off = (uint32_t)(sbuf->sb_rptr - sbuf->sb_data);
902: qemu_put_sbe32(f, off);
903: qemu_put_buffer(f, (unsigned char*)sbuf->sb_data, sbuf->sb_datalen);
904: }
905:
906: static void slirp_socket_save(QEMUFile *f, struct socket *so)
907: {
908: qemu_put_be32(f, so->so_urgc);
909: qemu_put_be32(f, so->so_faddr.s_addr);
910: qemu_put_be32(f, so->so_laddr.s_addr);
911: qemu_put_be16(f, so->so_fport);
912: qemu_put_be16(f, so->so_lport);
913: qemu_put_byte(f, so->so_iptos);
914: qemu_put_byte(f, so->so_emu);
915: qemu_put_byte(f, so->so_type);
916: qemu_put_be32(f, so->so_state);
917: slirp_sbuf_save(f, &so->so_rcv);
918: slirp_sbuf_save(f, &so->so_snd);
919: slirp_tcp_save(f, so->so_tcpcb);
920: }
921:
1.1.1.6 ! root 922: static void slirp_bootp_save(QEMUFile *f, Slirp *slirp)
! 923: {
! 924: int i;
! 925:
! 926: for (i = 0; i < NB_BOOTP_CLIENTS; i++) {
! 927: qemu_put_be16(f, slirp->bootp_clients[i].allocated);
! 928: qemu_put_buffer(f, slirp->bootp_clients[i].macaddr, 6);
! 929: }
! 930: }
! 931:
1.1.1.5 root 932: static void slirp_state_save(QEMUFile *f, void *opaque)
933: {
1.1.1.6 ! root 934: Slirp *slirp = opaque;
1.1.1.5 root 935: struct ex_list *ex_ptr;
936:
1.1.1.6 ! root 937: for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next)
1.1.1.5 root 938: if (ex_ptr->ex_pty == 3) {
939: struct socket *so;
1.1.1.6 ! root 940: so = slirp_find_ctl_socket(slirp, ex_ptr->ex_addr,
! 941: ntohs(ex_ptr->ex_fport));
1.1.1.5 root 942: if (!so)
943: continue;
944:
945: qemu_put_byte(f, 42);
946: slirp_socket_save(f, so);
947: }
948: qemu_put_byte(f, 0);
1.1.1.6 ! root 949:
! 950: qemu_put_be16(f, slirp->ip_id);
! 951:
! 952: slirp_bootp_save(f, slirp);
1.1.1.5 root 953: }
954:
955: static void slirp_tcp_load(QEMUFile *f, struct tcpcb *tp)
956: {
957: int i;
958:
959: tp->t_state = qemu_get_sbe16(f);
960: for (i = 0; i < TCPT_NTIMERS; i++)
961: tp->t_timer[i] = qemu_get_sbe16(f);
962: tp->t_rxtshift = qemu_get_sbe16(f);
963: tp->t_rxtcur = qemu_get_sbe16(f);
964: tp->t_dupacks = qemu_get_sbe16(f);
965: tp->t_maxseg = qemu_get_be16(f);
966: tp->t_force = qemu_get_sbyte(f);
967: tp->t_flags = qemu_get_be16(f);
968: tp->snd_una = qemu_get_be32(f);
969: tp->snd_nxt = qemu_get_be32(f);
970: tp->snd_up = qemu_get_be32(f);
971: tp->snd_wl1 = qemu_get_be32(f);
972: tp->snd_wl2 = qemu_get_be32(f);
973: tp->iss = qemu_get_be32(f);
974: tp->snd_wnd = qemu_get_be32(f);
975: tp->rcv_wnd = qemu_get_be32(f);
976: tp->rcv_nxt = qemu_get_be32(f);
977: tp->rcv_up = qemu_get_be32(f);
978: tp->irs = qemu_get_be32(f);
979: tp->rcv_adv = qemu_get_be32(f);
980: tp->snd_max = qemu_get_be32(f);
981: tp->snd_cwnd = qemu_get_be32(f);
982: tp->snd_ssthresh = qemu_get_be32(f);
983: tp->t_idle = qemu_get_sbe16(f);
984: tp->t_rtt = qemu_get_sbe16(f);
985: tp->t_rtseq = qemu_get_be32(f);
986: tp->t_srtt = qemu_get_sbe16(f);
987: tp->t_rttvar = qemu_get_sbe16(f);
988: tp->t_rttmin = qemu_get_be16(f);
989: tp->max_sndwnd = qemu_get_be32(f);
990: tp->t_oobflags = qemu_get_byte(f);
991: tp->t_iobc = qemu_get_byte(f);
992: tp->t_softerror = qemu_get_sbe16(f);
993: tp->snd_scale = qemu_get_byte(f);
994: tp->rcv_scale = qemu_get_byte(f);
995: tp->request_r_scale = qemu_get_byte(f);
996: tp->requested_s_scale = qemu_get_byte(f);
997: tp->ts_recent = qemu_get_be32(f);
998: tp->ts_recent_age = qemu_get_be32(f);
999: tp->last_ack_sent = qemu_get_be32(f);
1000: tcp_template(tp);
1001: }
1002:
1003: static int slirp_sbuf_load(QEMUFile *f, struct sbuf *sbuf)
1004: {
1005: uint32_t off, sb_cc, sb_datalen;
1006:
1007: sb_cc = qemu_get_be32(f);
1008: sb_datalen = qemu_get_be32(f);
1009:
1010: sbreserve(sbuf, sb_datalen);
1011:
1012: if (sbuf->sb_datalen != sb_datalen)
1013: return -ENOMEM;
1014:
1015: sbuf->sb_cc = sb_cc;
1016:
1017: off = qemu_get_sbe32(f);
1018: sbuf->sb_wptr = sbuf->sb_data + off;
1019: off = qemu_get_sbe32(f);
1020: sbuf->sb_rptr = sbuf->sb_data + off;
1021: qemu_get_buffer(f, (unsigned char*)sbuf->sb_data, sbuf->sb_datalen);
1022:
1023: return 0;
1024: }
1025:
1026: static int slirp_socket_load(QEMUFile *f, struct socket *so)
1027: {
1028: if (tcp_attach(so) < 0)
1029: return -ENOMEM;
1030:
1031: so->so_urgc = qemu_get_be32(f);
1032: so->so_faddr.s_addr = qemu_get_be32(f);
1033: so->so_laddr.s_addr = qemu_get_be32(f);
1034: so->so_fport = qemu_get_be16(f);
1035: so->so_lport = qemu_get_be16(f);
1036: so->so_iptos = qemu_get_byte(f);
1037: so->so_emu = qemu_get_byte(f);
1038: so->so_type = qemu_get_byte(f);
1039: so->so_state = qemu_get_be32(f);
1040: if (slirp_sbuf_load(f, &so->so_rcv) < 0)
1041: return -ENOMEM;
1042: if (slirp_sbuf_load(f, &so->so_snd) < 0)
1043: return -ENOMEM;
1044: slirp_tcp_load(f, so->so_tcpcb);
1045:
1046: return 0;
1047: }
1048:
1.1.1.6 ! root 1049: static void slirp_bootp_load(QEMUFile *f, Slirp *slirp)
! 1050: {
! 1051: int i;
! 1052:
! 1053: for (i = 0; i < NB_BOOTP_CLIENTS; i++) {
! 1054: slirp->bootp_clients[i].allocated = qemu_get_be16(f);
! 1055: qemu_get_buffer(f, slirp->bootp_clients[i].macaddr, 6);
! 1056: }
! 1057: }
! 1058:
1.1.1.5 root 1059: static int slirp_state_load(QEMUFile *f, void *opaque, int version_id)
1060: {
1.1.1.6 ! root 1061: Slirp *slirp = opaque;
1.1.1.5 root 1062: struct ex_list *ex_ptr;
1063: int r;
1064:
1065: while ((r = qemu_get_byte(f))) {
1066: int ret;
1.1.1.6 ! root 1067: struct socket *so = socreate(slirp);
1.1.1.5 root 1068:
1069: if (!so)
1070: return -ENOMEM;
1071:
1072: ret = slirp_socket_load(f, so);
1073:
1074: if (ret < 0)
1075: return ret;
1076:
1.1.1.6 ! root 1077: if ((so->so_faddr.s_addr & slirp->vnetwork_mask.s_addr) !=
! 1078: slirp->vnetwork_addr.s_addr) {
1.1.1.5 root 1079: return -EINVAL;
1.1.1.6 ! root 1080: }
! 1081: for (ex_ptr = slirp->exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) {
1.1.1.5 root 1082: if (ex_ptr->ex_pty == 3 &&
1.1.1.6 ! root 1083: so->so_faddr.s_addr == ex_ptr->ex_addr.s_addr &&
! 1084: so->so_fport == ex_ptr->ex_fport) {
1.1.1.5 root 1085: break;
1.1.1.6 ! root 1086: }
! 1087: }
1.1.1.5 root 1088: if (!ex_ptr)
1089: return -EINVAL;
1090:
1091: so->extra = (void *)ex_ptr->ex_exec;
1092: }
1093:
1.1.1.6 ! root 1094: if (version_id >= 2) {
! 1095: slirp->ip_id = qemu_get_be16(f);
! 1096: }
! 1097:
! 1098: if (version_id >= 3) {
! 1099: slirp_bootp_load(f, slirp);
! 1100: }
! 1101:
1.1.1.5 root 1102: return 0;
1103: }
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