root / slirp / slirp.c @ 3b46e624
History | View | Annotate | Download (16.2 kB)
| 1 |
#include "slirp.h" |
|---|---|
| 2 |
|
| 3 |
/* host address */
|
| 4 |
struct in_addr our_addr;
|
| 5 |
/* host dns address */
|
| 6 |
struct in_addr dns_addr;
|
| 7 |
/* host loopback address */
|
| 8 |
struct in_addr loopback_addr;
|
| 9 |
|
| 10 |
/* address for slirp virtual addresses */
|
| 11 |
struct in_addr special_addr;
|
| 12 |
/* virtual address alias for host */
|
| 13 |
struct in_addr alias_addr;
|
| 14 |
|
| 15 |
const uint8_t special_ethaddr[6] = { |
| 16 |
0x52, 0x54, 0x00, 0x12, 0x35, 0x00 |
| 17 |
}; |
| 18 |
|
| 19 |
uint8_t client_ethaddr[6];
|
| 20 |
|
| 21 |
int do_slowtimo;
|
| 22 |
int link_up;
|
| 23 |
struct timeval tt;
|
| 24 |
FILE *lfd; |
| 25 |
struct ex_list *exec_list;
|
| 26 |
|
| 27 |
/* XXX: suppress those select globals */
|
| 28 |
fd_set *global_readfds, *global_writefds, *global_xfds; |
| 29 |
|
| 30 |
char slirp_hostname[33]; |
| 31 |
|
| 32 |
#ifdef _WIN32
|
| 33 |
|
| 34 |
static int get_dns_addr(struct in_addr *pdns_addr) |
| 35 |
{
|
| 36 |
FIXED_INFO *FixedInfo=NULL;
|
| 37 |
ULONG BufLen; |
| 38 |
DWORD ret; |
| 39 |
IP_ADDR_STRING *pIPAddr; |
| 40 |
struct in_addr tmp_addr;
|
| 41 |
|
| 42 |
FixedInfo = (FIXED_INFO *)GlobalAlloc(GPTR, sizeof(FIXED_INFO));
|
| 43 |
BufLen = sizeof(FIXED_INFO);
|
| 44 |
|
| 45 |
if (ERROR_BUFFER_OVERFLOW == GetNetworkParams(FixedInfo, &BufLen)) {
|
| 46 |
if (FixedInfo) {
|
| 47 |
GlobalFree(FixedInfo); |
| 48 |
FixedInfo = NULL;
|
| 49 |
} |
| 50 |
FixedInfo = GlobalAlloc(GPTR, BufLen); |
| 51 |
} |
| 52 |
|
| 53 |
if ((ret = GetNetworkParams(FixedInfo, &BufLen)) != ERROR_SUCCESS) {
|
| 54 |
printf("GetNetworkParams failed. ret = %08x\n", (u_int)ret );
|
| 55 |
if (FixedInfo) {
|
| 56 |
GlobalFree(FixedInfo); |
| 57 |
FixedInfo = NULL;
|
| 58 |
} |
| 59 |
return -1; |
| 60 |
} |
| 61 |
|
| 62 |
pIPAddr = &(FixedInfo->DnsServerList); |
| 63 |
inet_aton(pIPAddr->IpAddress.String, &tmp_addr); |
| 64 |
*pdns_addr = tmp_addr; |
| 65 |
#if 0
|
| 66 |
printf( "DNS Servers:\n" );
|
| 67 |
printf( "DNS Addr:%s\n", pIPAddr->IpAddress.String );
|
| 68 |
|
| 69 |
pIPAddr = FixedInfo -> DnsServerList.Next;
|
| 70 |
while ( pIPAddr ) {
|
| 71 |
printf( "DNS Addr:%s\n", pIPAddr ->IpAddress.String );
|
| 72 |
pIPAddr = pIPAddr ->Next;
|
| 73 |
}
|
| 74 |
#endif
|
| 75 |
if (FixedInfo) {
|
| 76 |
GlobalFree(FixedInfo); |
| 77 |
FixedInfo = NULL;
|
| 78 |
} |
| 79 |
return 0; |
| 80 |
} |
| 81 |
|
| 82 |
#else
|
| 83 |
|
| 84 |
static int get_dns_addr(struct in_addr *pdns_addr) |
| 85 |
{
|
| 86 |
char buff[512]; |
| 87 |
char buff2[256]; |
| 88 |
FILE *f; |
| 89 |
int found = 0; |
| 90 |
struct in_addr tmp_addr;
|
| 91 |
|
| 92 |
f = fopen("/etc/resolv.conf", "r"); |
| 93 |
if (!f)
|
| 94 |
return -1; |
| 95 |
|
| 96 |
lprint("IP address of your DNS(s): ");
|
| 97 |
while (fgets(buff, 512, f) != NULL) { |
| 98 |
if (sscanf(buff, "nameserver%*[ \t]%256s", buff2) == 1) { |
| 99 |
if (!inet_aton(buff2, &tmp_addr))
|
| 100 |
continue;
|
| 101 |
if (tmp_addr.s_addr == loopback_addr.s_addr)
|
| 102 |
tmp_addr = our_addr; |
| 103 |
/* If it's the first one, set it to dns_addr */
|
| 104 |
if (!found)
|
| 105 |
*pdns_addr = tmp_addr; |
| 106 |
else
|
| 107 |
lprint(", ");
|
| 108 |
if (++found > 3) { |
| 109 |
lprint("(more)");
|
| 110 |
break;
|
| 111 |
} else
|
| 112 |
lprint("%s", inet_ntoa(tmp_addr));
|
| 113 |
} |
| 114 |
} |
| 115 |
fclose(f); |
| 116 |
if (!found)
|
| 117 |
return -1; |
| 118 |
return 0; |
| 119 |
} |
| 120 |
|
| 121 |
#endif
|
| 122 |
|
| 123 |
#ifdef _WIN32
|
| 124 |
void slirp_cleanup(void) |
| 125 |
{
|
| 126 |
WSACleanup(); |
| 127 |
} |
| 128 |
#endif
|
| 129 |
|
| 130 |
void slirp_init(void) |
| 131 |
{
|
| 132 |
// debug_init("/tmp/slirp.log", DEBUG_DEFAULT);
|
| 133 |
|
| 134 |
#ifdef _WIN32
|
| 135 |
{
|
| 136 |
WSADATA Data; |
| 137 |
WSAStartup(MAKEWORD(2,0), &Data); |
| 138 |
atexit(slirp_cleanup); |
| 139 |
} |
| 140 |
#endif
|
| 141 |
|
| 142 |
link_up = 1;
|
| 143 |
|
| 144 |
if_init(); |
| 145 |
ip_init(); |
| 146 |
|
| 147 |
/* Initialise mbufs *after* setting the MTU */
|
| 148 |
m_init(); |
| 149 |
|
| 150 |
/* set default addresses */
|
| 151 |
inet_aton("127.0.0.1", &loopback_addr);
|
| 152 |
|
| 153 |
if (get_dns_addr(&dns_addr) < 0) { |
| 154 |
dns_addr = loopback_addr; |
| 155 |
fprintf (stderr, "Warning: No DNS servers found\n");
|
| 156 |
} |
| 157 |
|
| 158 |
inet_aton(CTL_SPECIAL, &special_addr); |
| 159 |
alias_addr.s_addr = special_addr.s_addr | htonl(CTL_ALIAS); |
| 160 |
getouraddr(); |
| 161 |
} |
| 162 |
|
| 163 |
#define CONN_CANFSEND(so) (((so)->so_state & (SS_FCANTSENDMORE|SS_ISFCONNECTED)) == SS_ISFCONNECTED)
|
| 164 |
#define CONN_CANFRCV(so) (((so)->so_state & (SS_FCANTRCVMORE|SS_ISFCONNECTED)) == SS_ISFCONNECTED)
|
| 165 |
#define UPD_NFDS(x) if (nfds < (x)) nfds = (x) |
| 166 |
|
| 167 |
/*
|
| 168 |
* curtime kept to an accuracy of 1ms
|
| 169 |
*/
|
| 170 |
#ifdef _WIN32
|
| 171 |
static void updtime(void) |
| 172 |
{
|
| 173 |
struct _timeb tb;
|
| 174 |
|
| 175 |
_ftime(&tb); |
| 176 |
curtime = (u_int)tb.time * (u_int)1000;
|
| 177 |
curtime += (u_int)tb.millitm; |
| 178 |
} |
| 179 |
#else
|
| 180 |
static void updtime(void) |
| 181 |
{
|
| 182 |
gettimeofday(&tt, 0);
|
| 183 |
|
| 184 |
curtime = (u_int)tt.tv_sec * (u_int)1000;
|
| 185 |
curtime += (u_int)tt.tv_usec / (u_int)1000;
|
| 186 |
|
| 187 |
if ((tt.tv_usec % 1000) >= 500) |
| 188 |
curtime++; |
| 189 |
} |
| 190 |
#endif
|
| 191 |
|
| 192 |
void slirp_select_fill(int *pnfds, |
| 193 |
fd_set *readfds, fd_set *writefds, fd_set *xfds) |
| 194 |
{
|
| 195 |
struct socket *so, *so_next;
|
| 196 |
struct timeval timeout;
|
| 197 |
int nfds;
|
| 198 |
int tmp_time;
|
| 199 |
|
| 200 |
/* fail safe */
|
| 201 |
global_readfds = NULL;
|
| 202 |
global_writefds = NULL;
|
| 203 |
global_xfds = NULL;
|
| 204 |
|
| 205 |
nfds = *pnfds; |
| 206 |
/*
|
| 207 |
* First, TCP sockets
|
| 208 |
*/
|
| 209 |
do_slowtimo = 0;
|
| 210 |
if (link_up) {
|
| 211 |
/*
|
| 212 |
* *_slowtimo needs calling if there are IP fragments
|
| 213 |
* in the fragment queue, or there are TCP connections active
|
| 214 |
*/
|
| 215 |
do_slowtimo = ((tcb.so_next != &tcb) || |
| 216 |
((struct ipasfrag *)&ipq != (struct ipasfrag *)ipq.next)); |
| 217 |
|
| 218 |
for (so = tcb.so_next; so != &tcb; so = so_next) {
|
| 219 |
so_next = so->so_next; |
| 220 |
|
| 221 |
/*
|
| 222 |
* See if we need a tcp_fasttimo
|
| 223 |
*/
|
| 224 |
if (time_fasttimo == 0 && so->so_tcpcb->t_flags & TF_DELACK) |
| 225 |
time_fasttimo = curtime; /* Flag when we want a fasttimo */
|
| 226 |
|
| 227 |
/*
|
| 228 |
* NOFDREF can include still connecting to local-host,
|
| 229 |
* newly socreated() sockets etc. Don't want to select these.
|
| 230 |
*/
|
| 231 |
if (so->so_state & SS_NOFDREF || so->s == -1) |
| 232 |
continue;
|
| 233 |
|
| 234 |
/*
|
| 235 |
* Set for reading sockets which are accepting
|
| 236 |
*/
|
| 237 |
if (so->so_state & SS_FACCEPTCONN) {
|
| 238 |
FD_SET(so->s, readfds); |
| 239 |
UPD_NFDS(so->s); |
| 240 |
continue;
|
| 241 |
} |
| 242 |
|
| 243 |
/*
|
| 244 |
* Set for writing sockets which are connecting
|
| 245 |
*/
|
| 246 |
if (so->so_state & SS_ISFCONNECTING) {
|
| 247 |
FD_SET(so->s, writefds); |
| 248 |
UPD_NFDS(so->s); |
| 249 |
continue;
|
| 250 |
} |
| 251 |
|
| 252 |
/*
|
| 253 |
* Set for writing if we are connected, can send more, and
|
| 254 |
* we have something to send
|
| 255 |
*/
|
| 256 |
if (CONN_CANFSEND(so) && so->so_rcv.sb_cc) {
|
| 257 |
FD_SET(so->s, writefds); |
| 258 |
UPD_NFDS(so->s); |
| 259 |
} |
| 260 |
|
| 261 |
/*
|
| 262 |
* Set for reading (and urgent data) if we are connected, can
|
| 263 |
* receive more, and we have room for it XXX /2 ?
|
| 264 |
*/
|
| 265 |
if (CONN_CANFRCV(so) && (so->so_snd.sb_cc < (so->so_snd.sb_datalen/2))) { |
| 266 |
FD_SET(so->s, readfds); |
| 267 |
FD_SET(so->s, xfds); |
| 268 |
UPD_NFDS(so->s); |
| 269 |
} |
| 270 |
} |
| 271 |
|
| 272 |
/*
|
| 273 |
* UDP sockets
|
| 274 |
*/
|
| 275 |
for (so = udb.so_next; so != &udb; so = so_next) {
|
| 276 |
so_next = so->so_next; |
| 277 |
|
| 278 |
/*
|
| 279 |
* See if it's timed out
|
| 280 |
*/
|
| 281 |
if (so->so_expire) {
|
| 282 |
if (so->so_expire <= curtime) {
|
| 283 |
udp_detach(so); |
| 284 |
continue;
|
| 285 |
} else
|
| 286 |
do_slowtimo = 1; /* Let socket expire */ |
| 287 |
} |
| 288 |
|
| 289 |
/*
|
| 290 |
* When UDP packets are received from over the
|
| 291 |
* link, they're sendto()'d straight away, so
|
| 292 |
* no need for setting for writing
|
| 293 |
* Limit the number of packets queued by this session
|
| 294 |
* to 4. Note that even though we try and limit this
|
| 295 |
* to 4 packets, the session could have more queued
|
| 296 |
* if the packets needed to be fragmented
|
| 297 |
* (XXX <= 4 ?)
|
| 298 |
*/
|
| 299 |
if ((so->so_state & SS_ISFCONNECTED) && so->so_queued <= 4) { |
| 300 |
FD_SET(so->s, readfds); |
| 301 |
UPD_NFDS(so->s); |
| 302 |
} |
| 303 |
} |
| 304 |
} |
| 305 |
|
| 306 |
/*
|
| 307 |
* Setup timeout to use minimum CPU usage, especially when idle
|
| 308 |
*/
|
| 309 |
|
| 310 |
/*
|
| 311 |
* First, see the timeout needed by *timo
|
| 312 |
*/
|
| 313 |
timeout.tv_sec = 0;
|
| 314 |
timeout.tv_usec = -1;
|
| 315 |
/*
|
| 316 |
* If a slowtimo is needed, set timeout to 500ms from the last
|
| 317 |
* slow timeout. If a fast timeout is needed, set timeout within
|
| 318 |
* 200ms of when it was requested.
|
| 319 |
*/
|
| 320 |
if (do_slowtimo) {
|
| 321 |
/* XXX + 10000 because some select()'s aren't that accurate */
|
| 322 |
timeout.tv_usec = ((500 - (curtime - last_slowtimo)) * 1000) + 10000; |
| 323 |
if (timeout.tv_usec < 0) |
| 324 |
timeout.tv_usec = 0;
|
| 325 |
else if (timeout.tv_usec > 510000) |
| 326 |
timeout.tv_usec = 510000;
|
| 327 |
|
| 328 |
/* Can only fasttimo if we also slowtimo */
|
| 329 |
if (time_fasttimo) {
|
| 330 |
tmp_time = (200 - (curtime - time_fasttimo)) * 1000; |
| 331 |
if (tmp_time < 0) |
| 332 |
tmp_time = 0;
|
| 333 |
|
| 334 |
/* Choose the smallest of the 2 */
|
| 335 |
if (tmp_time < timeout.tv_usec)
|
| 336 |
timeout.tv_usec = (u_int)tmp_time; |
| 337 |
} |
| 338 |
} |
| 339 |
*pnfds = nfds; |
| 340 |
} |
| 341 |
|
| 342 |
void slirp_select_poll(fd_set *readfds, fd_set *writefds, fd_set *xfds)
|
| 343 |
{
|
| 344 |
struct socket *so, *so_next;
|
| 345 |
int ret;
|
| 346 |
|
| 347 |
global_readfds = readfds; |
| 348 |
global_writefds = writefds; |
| 349 |
global_xfds = xfds; |
| 350 |
|
| 351 |
/* Update time */
|
| 352 |
updtime(); |
| 353 |
|
| 354 |
/*
|
| 355 |
* See if anything has timed out
|
| 356 |
*/
|
| 357 |
if (link_up) {
|
| 358 |
if (time_fasttimo && ((curtime - time_fasttimo) >= 2)) { |
| 359 |
tcp_fasttimo(); |
| 360 |
time_fasttimo = 0;
|
| 361 |
} |
| 362 |
if (do_slowtimo && ((curtime - last_slowtimo) >= 499)) { |
| 363 |
ip_slowtimo(); |
| 364 |
tcp_slowtimo(); |
| 365 |
last_slowtimo = curtime; |
| 366 |
} |
| 367 |
} |
| 368 |
|
| 369 |
/*
|
| 370 |
* Check sockets
|
| 371 |
*/
|
| 372 |
if (link_up) {
|
| 373 |
/*
|
| 374 |
* Check TCP sockets
|
| 375 |
*/
|
| 376 |
for (so = tcb.so_next; so != &tcb; so = so_next) {
|
| 377 |
so_next = so->so_next; |
| 378 |
|
| 379 |
/*
|
| 380 |
* FD_ISSET is meaningless on these sockets
|
| 381 |
* (and they can crash the program)
|
| 382 |
*/
|
| 383 |
if (so->so_state & SS_NOFDREF || so->s == -1) |
| 384 |
continue;
|
| 385 |
|
| 386 |
/*
|
| 387 |
* Check for URG data
|
| 388 |
* This will soread as well, so no need to
|
| 389 |
* test for readfds below if this succeeds
|
| 390 |
*/
|
| 391 |
if (FD_ISSET(so->s, xfds))
|
| 392 |
sorecvoob(so); |
| 393 |
/*
|
| 394 |
* Check sockets for reading
|
| 395 |
*/
|
| 396 |
else if (FD_ISSET(so->s, readfds)) { |
| 397 |
/*
|
| 398 |
* Check for incoming connections
|
| 399 |
*/
|
| 400 |
if (so->so_state & SS_FACCEPTCONN) {
|
| 401 |
tcp_connect(so); |
| 402 |
continue;
|
| 403 |
} /* else */
|
| 404 |
ret = soread(so); |
| 405 |
|
| 406 |
/* Output it if we read something */
|
| 407 |
if (ret > 0) |
| 408 |
tcp_output(sototcpcb(so)); |
| 409 |
} |
| 410 |
|
| 411 |
/*
|
| 412 |
* Check sockets for writing
|
| 413 |
*/
|
| 414 |
if (FD_ISSET(so->s, writefds)) {
|
| 415 |
/*
|
| 416 |
* Check for non-blocking, still-connecting sockets
|
| 417 |
*/
|
| 418 |
if (so->so_state & SS_ISFCONNECTING) {
|
| 419 |
/* Connected */
|
| 420 |
so->so_state &= ~SS_ISFCONNECTING; |
| 421 |
|
| 422 |
ret = send(so->s, &ret, 0, 0); |
| 423 |
if (ret < 0) { |
| 424 |
/* XXXXX Must fix, zero bytes is a NOP */
|
| 425 |
if (errno == EAGAIN || errno == EWOULDBLOCK ||
|
| 426 |
errno == EINPROGRESS || errno == ENOTCONN) |
| 427 |
continue;
|
| 428 |
|
| 429 |
/* else failed */
|
| 430 |
so->so_state = SS_NOFDREF; |
| 431 |
} |
| 432 |
/* else so->so_state &= ~SS_ISFCONNECTING; */
|
| 433 |
|
| 434 |
/*
|
| 435 |
* Continue tcp_input
|
| 436 |
*/
|
| 437 |
tcp_input((struct mbuf *)NULL, sizeof(struct ip), so); |
| 438 |
/* continue; */
|
| 439 |
} else
|
| 440 |
ret = sowrite(so); |
| 441 |
/*
|
| 442 |
* XXXXX If we wrote something (a lot), there
|
| 443 |
* could be a need for a window update.
|
| 444 |
* In the worst case, the remote will send
|
| 445 |
* a window probe to get things going again
|
| 446 |
*/
|
| 447 |
} |
| 448 |
|
| 449 |
/*
|
| 450 |
* Probe a still-connecting, non-blocking socket
|
| 451 |
* to check if it's still alive
|
| 452 |
*/
|
| 453 |
#ifdef PROBE_CONN
|
| 454 |
if (so->so_state & SS_ISFCONNECTING) {
|
| 455 |
ret = recv(so->s, (char *)&ret, 0,0); |
| 456 |
|
| 457 |
if (ret < 0) { |
| 458 |
/* XXX */
|
| 459 |
if (errno == EAGAIN || errno == EWOULDBLOCK ||
|
| 460 |
errno == EINPROGRESS || errno == ENOTCONN) |
| 461 |
continue; /* Still connecting, continue */ |
| 462 |
|
| 463 |
/* else failed */
|
| 464 |
so->so_state = SS_NOFDREF; |
| 465 |
|
| 466 |
/* tcp_input will take care of it */
|
| 467 |
} else {
|
| 468 |
ret = send(so->s, &ret, 0,0); |
| 469 |
if (ret < 0) { |
| 470 |
/* XXX */
|
| 471 |
if (errno == EAGAIN || errno == EWOULDBLOCK ||
|
| 472 |
errno == EINPROGRESS || errno == ENOTCONN) |
| 473 |
continue;
|
| 474 |
/* else failed */
|
| 475 |
so->so_state = SS_NOFDREF; |
| 476 |
} else
|
| 477 |
so->so_state &= ~SS_ISFCONNECTING; |
| 478 |
|
| 479 |
} |
| 480 |
tcp_input((struct mbuf *)NULL, sizeof(struct ip),so); |
| 481 |
} /* SS_ISFCONNECTING */
|
| 482 |
#endif
|
| 483 |
} |
| 484 |
|
| 485 |
/*
|
| 486 |
* Now UDP sockets.
|
| 487 |
* Incoming packets are sent straight away, they're not buffered.
|
| 488 |
* Incoming UDP data isn't buffered either.
|
| 489 |
*/
|
| 490 |
for (so = udb.so_next; so != &udb; so = so_next) {
|
| 491 |
so_next = so->so_next; |
| 492 |
|
| 493 |
if (so->s != -1 && FD_ISSET(so->s, readfds)) { |
| 494 |
sorecvfrom(so); |
| 495 |
} |
| 496 |
} |
| 497 |
} |
| 498 |
|
| 499 |
/*
|
| 500 |
* See if we can start outputting
|
| 501 |
*/
|
| 502 |
if (if_queued && link_up)
|
| 503 |
if_start(); |
| 504 |
|
| 505 |
/* clear global file descriptor sets.
|
| 506 |
* these reside on the stack in vl.c
|
| 507 |
* so they're unusable if we're not in
|
| 508 |
* slirp_select_fill or slirp_select_poll.
|
| 509 |
*/
|
| 510 |
global_readfds = NULL;
|
| 511 |
global_writefds = NULL;
|
| 512 |
global_xfds = NULL;
|
| 513 |
} |
| 514 |
|
| 515 |
#define ETH_ALEN 6 |
| 516 |
#define ETH_HLEN 14 |
| 517 |
|
| 518 |
#define ETH_P_IP 0x0800 /* Internet Protocol packet */ |
| 519 |
#define ETH_P_ARP 0x0806 /* Address Resolution packet */ |
| 520 |
|
| 521 |
#define ARPOP_REQUEST 1 /* ARP request */ |
| 522 |
#define ARPOP_REPLY 2 /* ARP reply */ |
| 523 |
|
| 524 |
struct ethhdr
|
| 525 |
{
|
| 526 |
unsigned char h_dest[ETH_ALEN]; /* destination eth addr */ |
| 527 |
unsigned char h_source[ETH_ALEN]; /* source ether addr */ |
| 528 |
unsigned short h_proto; /* packet type ID field */ |
| 529 |
}; |
| 530 |
|
| 531 |
struct arphdr
|
| 532 |
{
|
| 533 |
unsigned short ar_hrd; /* format of hardware address */ |
| 534 |
unsigned short ar_pro; /* format of protocol address */ |
| 535 |
unsigned char ar_hln; /* length of hardware address */ |
| 536 |
unsigned char ar_pln; /* length of protocol address */ |
| 537 |
unsigned short ar_op; /* ARP opcode (command) */ |
| 538 |
|
| 539 |
/*
|
| 540 |
* Ethernet looks like this : This bit is variable sized however...
|
| 541 |
*/
|
| 542 |
unsigned char ar_sha[ETH_ALEN]; /* sender hardware address */ |
| 543 |
unsigned char ar_sip[4]; /* sender IP address */ |
| 544 |
unsigned char ar_tha[ETH_ALEN]; /* target hardware address */ |
| 545 |
unsigned char ar_tip[4]; /* target IP address */ |
| 546 |
}; |
| 547 |
|
| 548 |
void arp_input(const uint8_t *pkt, int pkt_len) |
| 549 |
{
|
| 550 |
struct ethhdr *eh = (struct ethhdr *)pkt; |
| 551 |
struct arphdr *ah = (struct arphdr *)(pkt + ETH_HLEN); |
| 552 |
uint8_t arp_reply[ETH_HLEN + sizeof(struct arphdr)]; |
| 553 |
struct ethhdr *reh = (struct ethhdr *)arp_reply; |
| 554 |
struct arphdr *rah = (struct arphdr *)(arp_reply + ETH_HLEN); |
| 555 |
int ar_op;
|
| 556 |
struct ex_list *ex_ptr;
|
| 557 |
|
| 558 |
ar_op = ntohs(ah->ar_op); |
| 559 |
switch(ar_op) {
|
| 560 |
case ARPOP_REQUEST:
|
| 561 |
if (!memcmp(ah->ar_tip, &special_addr, 3)) { |
| 562 |
if (ah->ar_tip[3] == CTL_DNS || ah->ar_tip[3] == CTL_ALIAS) |
| 563 |
goto arp_ok;
|
| 564 |
for (ex_ptr = exec_list; ex_ptr; ex_ptr = ex_ptr->ex_next) {
|
| 565 |
if (ex_ptr->ex_addr == ah->ar_tip[3]) |
| 566 |
goto arp_ok;
|
| 567 |
} |
| 568 |
return;
|
| 569 |
arp_ok:
|
| 570 |
/* XXX: make an ARP request to have the client address */
|
| 571 |
memcpy(client_ethaddr, eh->h_source, ETH_ALEN); |
| 572 |
|
| 573 |
/* ARP request for alias/dns mac address */
|
| 574 |
memcpy(reh->h_dest, pkt + ETH_ALEN, ETH_ALEN); |
| 575 |
memcpy(reh->h_source, special_ethaddr, ETH_ALEN - 1);
|
| 576 |
reh->h_source[5] = ah->ar_tip[3]; |
| 577 |
reh->h_proto = htons(ETH_P_ARP); |
| 578 |
|
| 579 |
rah->ar_hrd = htons(1);
|
| 580 |
rah->ar_pro = htons(ETH_P_IP); |
| 581 |
rah->ar_hln = ETH_ALEN; |
| 582 |
rah->ar_pln = 4;
|
| 583 |
rah->ar_op = htons(ARPOP_REPLY); |
| 584 |
memcpy(rah->ar_sha, reh->h_source, ETH_ALEN); |
| 585 |
memcpy(rah->ar_sip, ah->ar_tip, 4);
|
| 586 |
memcpy(rah->ar_tha, ah->ar_sha, ETH_ALEN); |
| 587 |
memcpy(rah->ar_tip, ah->ar_sip, 4);
|
| 588 |
slirp_output(arp_reply, sizeof(arp_reply));
|
| 589 |
} |
| 590 |
break;
|
| 591 |
default:
|
| 592 |
break;
|
| 593 |
} |
| 594 |
} |
| 595 |
|
| 596 |
void slirp_input(const uint8_t *pkt, int pkt_len) |
| 597 |
{
|
| 598 |
struct mbuf *m;
|
| 599 |
int proto;
|
| 600 |
|
| 601 |
if (pkt_len < ETH_HLEN)
|
| 602 |
return;
|
| 603 |
|
| 604 |
proto = ntohs(*(uint16_t *)(pkt + 12));
|
| 605 |
switch(proto) {
|
| 606 |
case ETH_P_ARP:
|
| 607 |
arp_input(pkt, pkt_len); |
| 608 |
break;
|
| 609 |
case ETH_P_IP:
|
| 610 |
m = m_get(); |
| 611 |
if (!m)
|
| 612 |
return;
|
| 613 |
/* Note: we add to align the IP header */
|
| 614 |
m->m_len = pkt_len + 2;
|
| 615 |
memcpy(m->m_data + 2, pkt, pkt_len);
|
| 616 |
|
| 617 |
m->m_data += 2 + ETH_HLEN;
|
| 618 |
m->m_len -= 2 + ETH_HLEN;
|
| 619 |
|
| 620 |
ip_input(m); |
| 621 |
break;
|
| 622 |
default:
|
| 623 |
break;
|
| 624 |
} |
| 625 |
} |
| 626 |
|
| 627 |
/* output the IP packet to the ethernet device */
|
| 628 |
void if_encap(const uint8_t *ip_data, int ip_data_len) |
| 629 |
{
|
| 630 |
uint8_t buf[1600];
|
| 631 |
struct ethhdr *eh = (struct ethhdr *)buf; |
| 632 |
|
| 633 |
if (ip_data_len + ETH_HLEN > sizeof(buf)) |
| 634 |
return;
|
| 635 |
|
| 636 |
memcpy(eh->h_dest, client_ethaddr, ETH_ALEN); |
| 637 |
memcpy(eh->h_source, special_ethaddr, ETH_ALEN - 1);
|
| 638 |
/* XXX: not correct */
|
| 639 |
eh->h_source[5] = CTL_ALIAS;
|
| 640 |
eh->h_proto = htons(ETH_P_IP); |
| 641 |
memcpy(buf + sizeof(struct ethhdr), ip_data, ip_data_len); |
| 642 |
slirp_output(buf, ip_data_len + ETH_HLEN); |
| 643 |
} |
| 644 |
|
| 645 |
int slirp_redir(int is_udp, int host_port, |
| 646 |
struct in_addr guest_addr, int guest_port) |
| 647 |
{
|
| 648 |
if (is_udp) {
|
| 649 |
if (!udp_listen(htons(host_port), guest_addr.s_addr,
|
| 650 |
htons(guest_port), 0))
|
| 651 |
return -1; |
| 652 |
} else {
|
| 653 |
if (!solisten(htons(host_port), guest_addr.s_addr,
|
| 654 |
htons(guest_port), 0))
|
| 655 |
return -1; |
| 656 |
} |
| 657 |
return 0; |
| 658 |
} |
| 659 |
|
| 660 |
int slirp_add_exec(int do_pty, const char *args, int addr_low_byte, |
| 661 |
int guest_port)
|
| 662 |
{
|
| 663 |
return add_exec(&exec_list, do_pty, (char *)args, |
| 664 |
addr_low_byte, htons(guest_port)); |
| 665 |
} |