| 1 | /* |
| 2 | * Unix networking abstraction. |
| 3 | */ |
| 4 | |
| 5 | #include <stdio.h> |
| 6 | #include <stdlib.h> |
| 7 | #include <assert.h> |
| 8 | #include <errno.h> |
| 9 | #include <fcntl.h> |
| 10 | #include <unistd.h> |
| 11 | #include <sys/types.h> |
| 12 | #include <sys/socket.h> |
| 13 | #include <sys/ioctl.h> |
| 14 | #include <arpa/inet.h> |
| 15 | #include <netinet/in.h> |
| 16 | #include <netinet/tcp.h> |
| 17 | #include <netdb.h> |
| 18 | #include <sys/un.h> |
| 19 | |
| 20 | #define DEFINE_PLUG_METHOD_MACROS |
| 21 | #include "putty.h" |
| 22 | #include "network.h" |
| 23 | #include "tree234.h" |
| 24 | |
| 25 | /* Solaris needs <sys/sockio.h> for SIOCATMARK. */ |
| 26 | #ifndef SIOCATMARK |
| 27 | #include <sys/sockio.h> |
| 28 | #endif |
| 29 | |
| 30 | #ifndef X11_UNIX_PATH |
| 31 | # define X11_UNIX_PATH "/tmp/.X11-unix/X" |
| 32 | #endif |
| 33 | |
| 34 | /* |
| 35 | * Access to sockaddr types without breaking C strict aliasing rules. |
| 36 | */ |
| 37 | union sockaddr_union { |
| 38 | #ifdef NO_IPV6 |
| 39 | struct sockaddr_in storage; |
| 40 | #else |
| 41 | struct sockaddr_storage storage; |
| 42 | struct sockaddr_in6 sin6; |
| 43 | #endif |
| 44 | struct sockaddr sa; |
| 45 | struct sockaddr_in sin; |
| 46 | struct sockaddr_un su; |
| 47 | }; |
| 48 | |
| 49 | /* |
| 50 | * We used to typedef struct Socket_tag *Socket. |
| 51 | * |
| 52 | * Since we have made the networking abstraction slightly more |
| 53 | * abstract, Socket no longer means a tcp socket (it could mean |
| 54 | * an ssl socket). So now we must use Actual_Socket when we know |
| 55 | * we are talking about a tcp socket. |
| 56 | */ |
| 57 | typedef struct Socket_tag *Actual_Socket; |
| 58 | |
| 59 | /* |
| 60 | * Mutable state that goes with a SockAddr: stores information |
| 61 | * about where in the list of candidate IP(v*) addresses we've |
| 62 | * currently got to. |
| 63 | */ |
| 64 | typedef struct SockAddrStep_tag SockAddrStep; |
| 65 | struct SockAddrStep_tag { |
| 66 | #ifndef NO_IPV6 |
| 67 | struct addrinfo *ai; /* steps along addr->ais */ |
| 68 | #endif |
| 69 | int curraddr; |
| 70 | }; |
| 71 | |
| 72 | struct Socket_tag { |
| 73 | struct socket_function_table *fn; |
| 74 | /* the above variable absolutely *must* be the first in this structure */ |
| 75 | const char *error; |
| 76 | int s; |
| 77 | Plug plug; |
| 78 | void *private_ptr; |
| 79 | bufchain output_data; |
| 80 | int connected; /* irrelevant for listening sockets */ |
| 81 | int writable; |
| 82 | int frozen; /* this causes readability notifications to be ignored */ |
| 83 | int frozen_readable; /* this means we missed at least one readability |
| 84 | * notification while we were frozen */ |
| 85 | int localhost_only; /* for listening sockets */ |
| 86 | char oobdata[1]; |
| 87 | int sending_oob; |
| 88 | int oobpending; /* is there OOB data available to read? */ |
| 89 | int oobinline; |
| 90 | enum { EOF_NO, EOF_PENDING, EOF_SENT } outgoingeof; |
| 91 | int incomingeof; |
| 92 | int pending_error; /* in case send() returns error */ |
| 93 | int listener; |
| 94 | int nodelay, keepalive; /* for connect()-type sockets */ |
| 95 | int privport, port; /* and again */ |
| 96 | SockAddr addr; |
| 97 | SockAddrStep step; |
| 98 | /* |
| 99 | * We sometimes need pairs of Socket structures to be linked: |
| 100 | * if we are listening on the same IPv6 and v4 port, for |
| 101 | * example. So here we define `parent' and `child' pointers to |
| 102 | * track this link. |
| 103 | */ |
| 104 | Actual_Socket parent, child; |
| 105 | }; |
| 106 | |
| 107 | struct SockAddr_tag { |
| 108 | int refcount; |
| 109 | const char *error; |
| 110 | enum { UNRESOLVED, UNIX, IP } superfamily; |
| 111 | #ifndef NO_IPV6 |
| 112 | struct addrinfo *ais; /* Addresses IPv6 style. */ |
| 113 | #else |
| 114 | unsigned long *addresses; /* Addresses IPv4 style. */ |
| 115 | int naddresses; |
| 116 | #endif |
| 117 | char hostname[512]; /* Store an unresolved host name. */ |
| 118 | }; |
| 119 | |
| 120 | /* |
| 121 | * Which address family this address belongs to. AF_INET for IPv4; |
| 122 | * AF_INET6 for IPv6; AF_UNSPEC indicates that name resolution has |
| 123 | * not been done and a simple host name is held in this SockAddr |
| 124 | * structure. |
| 125 | */ |
| 126 | #ifndef NO_IPV6 |
| 127 | #define SOCKADDR_FAMILY(addr, step) \ |
| 128 | ((addr)->superfamily == UNRESOLVED ? AF_UNSPEC : \ |
| 129 | (addr)->superfamily == UNIX ? AF_UNIX : \ |
| 130 | (step).ai ? (step).ai->ai_family : AF_INET) |
| 131 | #else |
| 132 | #define SOCKADDR_FAMILY(addr, step) \ |
| 133 | ((addr)->superfamily == UNRESOLVED ? AF_UNSPEC : \ |
| 134 | (addr)->superfamily == UNIX ? AF_UNIX : AF_INET) |
| 135 | #endif |
| 136 | |
| 137 | /* |
| 138 | * Start a SockAddrStep structure to step through multiple |
| 139 | * addresses. |
| 140 | */ |
| 141 | #ifndef NO_IPV6 |
| 142 | #define START_STEP(addr, step) \ |
| 143 | ((step).ai = (addr)->ais, (step).curraddr = 0) |
| 144 | #else |
| 145 | #define START_STEP(addr, step) \ |
| 146 | ((step).curraddr = 0) |
| 147 | #endif |
| 148 | |
| 149 | static tree234 *sktree; |
| 150 | |
| 151 | static void uxsel_tell(Actual_Socket s); |
| 152 | |
| 153 | static int cmpfortree(void *av, void *bv) |
| 154 | { |
| 155 | Actual_Socket a = (Actual_Socket) av, b = (Actual_Socket) bv; |
| 156 | int as = a->s, bs = b->s; |
| 157 | if (as < bs) |
| 158 | return -1; |
| 159 | if (as > bs) |
| 160 | return +1; |
| 161 | if (a < b) |
| 162 | return -1; |
| 163 | if (a > b) |
| 164 | return +1; |
| 165 | return 0; |
| 166 | } |
| 167 | |
| 168 | static int cmpforsearch(void *av, void *bv) |
| 169 | { |
| 170 | Actual_Socket b = (Actual_Socket) bv; |
| 171 | int as = *(int *)av, bs = b->s; |
| 172 | if (as < bs) |
| 173 | return -1; |
| 174 | if (as > bs) |
| 175 | return +1; |
| 176 | return 0; |
| 177 | } |
| 178 | |
| 179 | void sk_init(void) |
| 180 | { |
| 181 | sktree = newtree234(cmpfortree); |
| 182 | } |
| 183 | |
| 184 | void sk_cleanup(void) |
| 185 | { |
| 186 | Actual_Socket s; |
| 187 | int i; |
| 188 | |
| 189 | if (sktree) { |
| 190 | for (i = 0; (s = index234(sktree, i)) != NULL; i++) { |
| 191 | close(s->s); |
| 192 | } |
| 193 | } |
| 194 | } |
| 195 | |
| 196 | SockAddr sk_namelookup(const char *host, char **canonicalname, int address_family) |
| 197 | { |
| 198 | SockAddr ret = snew(struct SockAddr_tag); |
| 199 | #ifndef NO_IPV6 |
| 200 | struct addrinfo hints; |
| 201 | int err; |
| 202 | #else |
| 203 | unsigned long a; |
| 204 | struct hostent *h = NULL; |
| 205 | int n; |
| 206 | #endif |
| 207 | char realhost[8192]; |
| 208 | |
| 209 | /* Clear the structure and default to IPv4. */ |
| 210 | memset(ret, 0, sizeof(struct SockAddr_tag)); |
| 211 | ret->superfamily = UNRESOLVED; |
| 212 | *realhost = '\0'; |
| 213 | ret->error = NULL; |
| 214 | ret->refcount = 1; |
| 215 | |
| 216 | #ifndef NO_IPV6 |
| 217 | hints.ai_flags = AI_CANONNAME; |
| 218 | hints.ai_family = (address_family == ADDRTYPE_IPV4 ? AF_INET : |
| 219 | address_family == ADDRTYPE_IPV6 ? AF_INET6 : |
| 220 | AF_UNSPEC); |
| 221 | hints.ai_socktype = SOCK_STREAM; |
| 222 | hints.ai_protocol = 0; |
| 223 | hints.ai_addrlen = 0; |
| 224 | hints.ai_addr = NULL; |
| 225 | hints.ai_canonname = NULL; |
| 226 | hints.ai_next = NULL; |
| 227 | err = getaddrinfo(host, NULL, &hints, &ret->ais); |
| 228 | if (err != 0) { |
| 229 | ret->error = gai_strerror(err); |
| 230 | return ret; |
| 231 | } |
| 232 | ret->superfamily = IP; |
| 233 | *realhost = '\0'; |
| 234 | if (ret->ais->ai_canonname != NULL) |
| 235 | strncat(realhost, ret->ais->ai_canonname, sizeof(realhost) - 1); |
| 236 | else |
| 237 | strncat(realhost, host, sizeof(realhost) - 1); |
| 238 | #else |
| 239 | if ((a = inet_addr(host)) == (unsigned long)(in_addr_t)(-1)) { |
| 240 | /* |
| 241 | * Otherwise use the IPv4-only gethostbyname... (NOTE: |
| 242 | * we don't use gethostbyname as a fallback!) |
| 243 | */ |
| 244 | if (ret->superfamily == UNRESOLVED) { |
| 245 | /*debug(("Resolving \"%s\" with gethostbyname() (IPv4 only)...\n", host)); */ |
| 246 | if ( (h = gethostbyname(host)) ) |
| 247 | ret->superfamily = IP; |
| 248 | } |
| 249 | if (ret->superfamily == UNRESOLVED) { |
| 250 | ret->error = (h_errno == HOST_NOT_FOUND || |
| 251 | h_errno == NO_DATA || |
| 252 | h_errno == NO_ADDRESS ? "Host does not exist" : |
| 253 | h_errno == TRY_AGAIN ? |
| 254 | "Temporary name service failure" : |
| 255 | "gethostbyname: unknown error"); |
| 256 | return ret; |
| 257 | } |
| 258 | /* This way we are always sure the h->h_name is valid :) */ |
| 259 | strncpy(realhost, h->h_name, sizeof(realhost)); |
| 260 | for (n = 0; h->h_addr_list[n]; n++); |
| 261 | ret->addresses = snewn(n, unsigned long); |
| 262 | ret->naddresses = n; |
| 263 | for (n = 0; n < ret->naddresses; n++) { |
| 264 | memcpy(&a, h->h_addr_list[n], sizeof(a)); |
| 265 | ret->addresses[n] = ntohl(a); |
| 266 | } |
| 267 | } else { |
| 268 | /* |
| 269 | * This must be a numeric IPv4 address because it caused a |
| 270 | * success return from inet_addr. |
| 271 | */ |
| 272 | ret->superfamily = IP; |
| 273 | strncpy(realhost, host, sizeof(realhost)); |
| 274 | ret->addresses = snew(unsigned long); |
| 275 | ret->naddresses = 1; |
| 276 | ret->addresses[0] = ntohl(a); |
| 277 | } |
| 278 | #endif |
| 279 | realhost[lenof(realhost)-1] = '\0'; |
| 280 | *canonicalname = snewn(1+strlen(realhost), char); |
| 281 | strcpy(*canonicalname, realhost); |
| 282 | return ret; |
| 283 | } |
| 284 | |
| 285 | SockAddr sk_nonamelookup(const char *host) |
| 286 | { |
| 287 | SockAddr ret = snew(struct SockAddr_tag); |
| 288 | ret->error = NULL; |
| 289 | ret->superfamily = UNRESOLVED; |
| 290 | strncpy(ret->hostname, host, lenof(ret->hostname)); |
| 291 | ret->hostname[lenof(ret->hostname)-1] = '\0'; |
| 292 | #ifndef NO_IPV6 |
| 293 | ret->ais = NULL; |
| 294 | #else |
| 295 | ret->addresses = NULL; |
| 296 | #endif |
| 297 | ret->refcount = 1; |
| 298 | return ret; |
| 299 | } |
| 300 | |
| 301 | static int sk_nextaddr(SockAddr addr, SockAddrStep *step) |
| 302 | { |
| 303 | #ifndef NO_IPV6 |
| 304 | if (step->ai && step->ai->ai_next) { |
| 305 | step->ai = step->ai->ai_next; |
| 306 | return TRUE; |
| 307 | } else |
| 308 | return FALSE; |
| 309 | #else |
| 310 | if (step->curraddr+1 < addr->naddresses) { |
| 311 | step->curraddr++; |
| 312 | return TRUE; |
| 313 | } else { |
| 314 | return FALSE; |
| 315 | } |
| 316 | #endif |
| 317 | } |
| 318 | |
| 319 | void sk_getaddr(SockAddr addr, char *buf, int buflen) |
| 320 | { |
| 321 | /* XXX not clear what we should return for Unix-domain sockets; let's |
| 322 | * hope the question never arises */ |
| 323 | assert(addr->superfamily != UNIX); |
| 324 | if (addr->superfamily == UNRESOLVED) { |
| 325 | strncpy(buf, addr->hostname, buflen); |
| 326 | buf[buflen-1] = '\0'; |
| 327 | } else { |
| 328 | #ifndef NO_IPV6 |
| 329 | if (getnameinfo(addr->ais->ai_addr, addr->ais->ai_addrlen, buf, buflen, |
| 330 | NULL, 0, NI_NUMERICHOST) != 0) { |
| 331 | buf[0] = '\0'; |
| 332 | strncat(buf, "<unknown>", buflen - 1); |
| 333 | } |
| 334 | #else |
| 335 | struct in_addr a; |
| 336 | SockAddrStep step; |
| 337 | START_STEP(addr, step); |
| 338 | assert(SOCKADDR_FAMILY(addr, step) == AF_INET); |
| 339 | a.s_addr = htonl(addr->addresses[0]); |
| 340 | strncpy(buf, inet_ntoa(a), buflen); |
| 341 | buf[buflen-1] = '\0'; |
| 342 | #endif |
| 343 | } |
| 344 | } |
| 345 | |
| 346 | int sk_hostname_is_local(char *name) |
| 347 | { |
| 348 | return !strcmp(name, "localhost") || |
| 349 | !strcmp(name, "::1") || |
| 350 | !strncmp(name, "127.", 4); |
| 351 | } |
| 352 | |
| 353 | #define ipv4_is_loopback(addr) \ |
| 354 | (((addr).s_addr & htonl(0xff000000)) == htonl(0x7f000000)) |
| 355 | |
| 356 | static int sockaddr_is_loopback(struct sockaddr *sa) |
| 357 | { |
| 358 | union sockaddr_union *u = (union sockaddr_union *)sa; |
| 359 | switch (u->sa.sa_family) { |
| 360 | case AF_INET: |
| 361 | return ipv4_is_loopback(u->sin.sin_addr); |
| 362 | #ifndef NO_IPV6 |
| 363 | case AF_INET6: |
| 364 | return IN6_IS_ADDR_LOOPBACK(&u->sin6.sin6_addr); |
| 365 | #endif |
| 366 | case AF_UNIX: |
| 367 | return TRUE; |
| 368 | default: |
| 369 | return FALSE; |
| 370 | } |
| 371 | } |
| 372 | |
| 373 | int sk_address_is_local(SockAddr addr) |
| 374 | { |
| 375 | if (addr->superfamily == UNRESOLVED) |
| 376 | return 0; /* we don't know; assume not */ |
| 377 | else if (addr->superfamily == UNIX) |
| 378 | return 1; |
| 379 | else { |
| 380 | #ifndef NO_IPV6 |
| 381 | return sockaddr_is_loopback(addr->ais->ai_addr); |
| 382 | #else |
| 383 | struct in_addr a; |
| 384 | SockAddrStep step; |
| 385 | START_STEP(addr, step); |
| 386 | assert(SOCKADDR_FAMILY(addr, step) == AF_INET); |
| 387 | a.s_addr = htonl(addr->addresses[0]); |
| 388 | return ipv4_is_loopback(a); |
| 389 | #endif |
| 390 | } |
| 391 | } |
| 392 | |
| 393 | int sk_addrtype(SockAddr addr) |
| 394 | { |
| 395 | SockAddrStep step; |
| 396 | int family; |
| 397 | START_STEP(addr, step); |
| 398 | family = SOCKADDR_FAMILY(addr, step); |
| 399 | |
| 400 | return (family == AF_INET ? ADDRTYPE_IPV4 : |
| 401 | #ifndef NO_IPV6 |
| 402 | family == AF_INET6 ? ADDRTYPE_IPV6 : |
| 403 | #endif |
| 404 | ADDRTYPE_NAME); |
| 405 | } |
| 406 | |
| 407 | void sk_addrcopy(SockAddr addr, char *buf) |
| 408 | { |
| 409 | SockAddrStep step; |
| 410 | int family; |
| 411 | START_STEP(addr, step); |
| 412 | family = SOCKADDR_FAMILY(addr, step); |
| 413 | |
| 414 | #ifndef NO_IPV6 |
| 415 | if (family == AF_INET) |
| 416 | memcpy(buf, &((struct sockaddr_in *)step.ai->ai_addr)->sin_addr, |
| 417 | sizeof(struct in_addr)); |
| 418 | else if (family == AF_INET6) |
| 419 | memcpy(buf, &((struct sockaddr_in6 *)step.ai->ai_addr)->sin6_addr, |
| 420 | sizeof(struct in6_addr)); |
| 421 | else |
| 422 | assert(FALSE); |
| 423 | #else |
| 424 | struct in_addr a; |
| 425 | |
| 426 | assert(family == AF_INET); |
| 427 | a.s_addr = htonl(addr->addresses[step.curraddr]); |
| 428 | memcpy(buf, (char*) &a.s_addr, 4); |
| 429 | #endif |
| 430 | } |
| 431 | |
| 432 | void sk_addr_free(SockAddr addr) |
| 433 | { |
| 434 | if (--addr->refcount > 0) |
| 435 | return; |
| 436 | #ifndef NO_IPV6 |
| 437 | if (addr->ais != NULL) |
| 438 | freeaddrinfo(addr->ais); |
| 439 | #else |
| 440 | sfree(addr->addresses); |
| 441 | #endif |
| 442 | sfree(addr); |
| 443 | } |
| 444 | |
| 445 | SockAddr sk_addr_dup(SockAddr addr) |
| 446 | { |
| 447 | addr->refcount++; |
| 448 | return addr; |
| 449 | } |
| 450 | |
| 451 | static Plug sk_tcp_plug(Socket sock, Plug p) |
| 452 | { |
| 453 | Actual_Socket s = (Actual_Socket) sock; |
| 454 | Plug ret = s->plug; |
| 455 | if (p) |
| 456 | s->plug = p; |
| 457 | return ret; |
| 458 | } |
| 459 | |
| 460 | static void sk_tcp_flush(Socket s) |
| 461 | { |
| 462 | /* |
| 463 | * We send data to the socket as soon as we can anyway, |
| 464 | * so we don't need to do anything here. :-) |
| 465 | */ |
| 466 | } |
| 467 | |
| 468 | static void sk_tcp_close(Socket s); |
| 469 | static int sk_tcp_write(Socket s, const char *data, int len); |
| 470 | static int sk_tcp_write_oob(Socket s, const char *data, int len); |
| 471 | static void sk_tcp_write_eof(Socket s); |
| 472 | static void sk_tcp_set_private_ptr(Socket s, void *ptr); |
| 473 | static void *sk_tcp_get_private_ptr(Socket s); |
| 474 | static void sk_tcp_set_frozen(Socket s, int is_frozen); |
| 475 | static const char *sk_tcp_socket_error(Socket s); |
| 476 | |
| 477 | static struct socket_function_table tcp_fn_table = { |
| 478 | sk_tcp_plug, |
| 479 | sk_tcp_close, |
| 480 | sk_tcp_write, |
| 481 | sk_tcp_write_oob, |
| 482 | sk_tcp_write_eof, |
| 483 | sk_tcp_flush, |
| 484 | sk_tcp_set_private_ptr, |
| 485 | sk_tcp_get_private_ptr, |
| 486 | sk_tcp_set_frozen, |
| 487 | sk_tcp_socket_error |
| 488 | }; |
| 489 | |
| 490 | Socket sk_register(OSSocket sockfd, Plug plug) |
| 491 | { |
| 492 | Actual_Socket ret; |
| 493 | |
| 494 | /* |
| 495 | * Create Socket structure. |
| 496 | */ |
| 497 | ret = snew(struct Socket_tag); |
| 498 | ret->fn = &tcp_fn_table; |
| 499 | ret->error = NULL; |
| 500 | ret->plug = plug; |
| 501 | bufchain_init(&ret->output_data); |
| 502 | ret->writable = 1; /* to start with */ |
| 503 | ret->sending_oob = 0; |
| 504 | ret->frozen = 1; |
| 505 | ret->frozen_readable = 0; |
| 506 | ret->localhost_only = 0; /* unused, but best init anyway */ |
| 507 | ret->pending_error = 0; |
| 508 | ret->oobpending = FALSE; |
| 509 | ret->outgoingeof = EOF_NO; |
| 510 | ret->incomingeof = FALSE; |
| 511 | ret->listener = 0; |
| 512 | ret->parent = ret->child = NULL; |
| 513 | ret->addr = NULL; |
| 514 | ret->connected = 1; |
| 515 | |
| 516 | ret->s = sockfd; |
| 517 | |
| 518 | if (ret->s < 0) { |
| 519 | ret->error = strerror(errno); |
| 520 | return (Socket) ret; |
| 521 | } |
| 522 | |
| 523 | ret->oobinline = 0; |
| 524 | |
| 525 | uxsel_tell(ret); |
| 526 | add234(sktree, ret); |
| 527 | |
| 528 | return (Socket) ret; |
| 529 | } |
| 530 | |
| 531 | static int try_connect(Actual_Socket sock) |
| 532 | { |
| 533 | int s; |
| 534 | union sockaddr_union u; |
| 535 | const union sockaddr_union *sa; |
| 536 | int err = 0; |
| 537 | short localport; |
| 538 | int fl, salen, family; |
| 539 | |
| 540 | /* |
| 541 | * Remove the socket from the tree before we overwrite its |
| 542 | * internal socket id, because that forms part of the tree's |
| 543 | * sorting criterion. We'll add it back before exiting this |
| 544 | * function, whether we changed anything or not. |
| 545 | */ |
| 546 | del234(sktree, sock); |
| 547 | |
| 548 | if (sock->s >= 0) |
| 549 | close(sock->s); |
| 550 | |
| 551 | plug_log(sock->plug, 0, sock->addr, sock->port, NULL, 0); |
| 552 | |
| 553 | /* |
| 554 | * Open socket. |
| 555 | */ |
| 556 | family = SOCKADDR_FAMILY(sock->addr, sock->step); |
| 557 | assert(family != AF_UNSPEC); |
| 558 | s = socket(family, SOCK_STREAM, 0); |
| 559 | sock->s = s; |
| 560 | |
| 561 | if (s < 0) { |
| 562 | err = errno; |
| 563 | goto ret; |
| 564 | } |
| 565 | |
| 566 | cloexec(s); |
| 567 | |
| 568 | if (sock->oobinline) { |
| 569 | int b = TRUE; |
| 570 | setsockopt(s, SOL_SOCKET, SO_OOBINLINE, (void *) &b, sizeof(b)); |
| 571 | } |
| 572 | |
| 573 | if (sock->nodelay) { |
| 574 | int b = TRUE; |
| 575 | setsockopt(s, IPPROTO_TCP, TCP_NODELAY, (void *) &b, sizeof(b)); |
| 576 | } |
| 577 | |
| 578 | if (sock->keepalive) { |
| 579 | int b = TRUE; |
| 580 | setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, (void *) &b, sizeof(b)); |
| 581 | } |
| 582 | |
| 583 | /* |
| 584 | * Bind to local address. |
| 585 | */ |
| 586 | if (sock->privport) |
| 587 | localport = 1023; /* count from 1023 downwards */ |
| 588 | else |
| 589 | localport = 0; /* just use port 0 (ie kernel picks) */ |
| 590 | |
| 591 | /* BSD IP stacks need sockaddr_in zeroed before filling in */ |
| 592 | memset(&u,'\0',sizeof(u)); |
| 593 | |
| 594 | /* We don't try to bind to a local address for UNIX domain sockets. (Why |
| 595 | * do we bother doing the bind when localport == 0 anyway?) */ |
| 596 | if (family != AF_UNIX) { |
| 597 | /* Loop round trying to bind */ |
| 598 | while (1) { |
| 599 | int retcode; |
| 600 | |
| 601 | #ifndef NO_IPV6 |
| 602 | if (family == AF_INET6) { |
| 603 | /* XXX use getaddrinfo to get a local address? */ |
| 604 | u.sin6.sin6_family = AF_INET6; |
| 605 | u.sin6.sin6_addr = in6addr_any; |
| 606 | u.sin6.sin6_port = htons(localport); |
| 607 | retcode = bind(s, &u.sa, sizeof(u.sin6)); |
| 608 | } else |
| 609 | #endif |
| 610 | { |
| 611 | assert(family == AF_INET); |
| 612 | u.sin.sin_family = AF_INET; |
| 613 | u.sin.sin_addr.s_addr = htonl(INADDR_ANY); |
| 614 | u.sin.sin_port = htons(localport); |
| 615 | retcode = bind(s, &u.sa, sizeof(u.sin)); |
| 616 | } |
| 617 | if (retcode >= 0) { |
| 618 | err = 0; |
| 619 | break; /* done */ |
| 620 | } else { |
| 621 | err = errno; |
| 622 | if (err != EADDRINUSE) /* failed, for a bad reason */ |
| 623 | break; |
| 624 | } |
| 625 | |
| 626 | if (localport == 0) |
| 627 | break; /* we're only looping once */ |
| 628 | localport--; |
| 629 | if (localport == 0) |
| 630 | break; /* we might have got to the end */ |
| 631 | } |
| 632 | |
| 633 | if (err) |
| 634 | goto ret; |
| 635 | } |
| 636 | |
| 637 | /* |
| 638 | * Connect to remote address. |
| 639 | */ |
| 640 | switch(family) { |
| 641 | #ifndef NO_IPV6 |
| 642 | case AF_INET: |
| 643 | /* XXX would be better to have got getaddrinfo() to fill in the port. */ |
| 644 | ((struct sockaddr_in *)sock->step.ai->ai_addr)->sin_port = |
| 645 | htons(sock->port); |
| 646 | sa = (const union sockaddr_union *)sock->step.ai->ai_addr; |
| 647 | salen = sock->step.ai->ai_addrlen; |
| 648 | break; |
| 649 | case AF_INET6: |
| 650 | ((struct sockaddr_in *)sock->step.ai->ai_addr)->sin_port = |
| 651 | htons(sock->port); |
| 652 | sa = (const union sockaddr_union *)sock->step.ai->ai_addr; |
| 653 | salen = sock->step.ai->ai_addrlen; |
| 654 | break; |
| 655 | #else |
| 656 | case AF_INET: |
| 657 | u.sin.sin_family = AF_INET; |
| 658 | u.sin.sin_addr.s_addr = htonl(sock->addr->addresses[sock->step.curraddr]); |
| 659 | u.sin.sin_port = htons((short) sock->port); |
| 660 | sa = &u; |
| 661 | salen = sizeof u.sin; |
| 662 | break; |
| 663 | #endif |
| 664 | case AF_UNIX: |
| 665 | assert(sock->port == 0); /* to catch confused people */ |
| 666 | assert(strlen(sock->addr->hostname) < sizeof u.su.sun_path); |
| 667 | u.su.sun_family = AF_UNIX; |
| 668 | strcpy(u.su.sun_path, sock->addr->hostname); |
| 669 | sa = &u; |
| 670 | salen = sizeof u.su; |
| 671 | break; |
| 672 | |
| 673 | default: |
| 674 | assert(0 && "unknown address family"); |
| 675 | exit(1); /* XXX: GCC doesn't understand assert() on some systems. */ |
| 676 | } |
| 677 | |
| 678 | fl = fcntl(s, F_GETFL); |
| 679 | if (fl != -1) |
| 680 | fcntl(s, F_SETFL, fl | O_NONBLOCK); |
| 681 | |
| 682 | if ((connect(s, &(sa->sa), salen)) < 0) { |
| 683 | if ( errno != EINPROGRESS ) { |
| 684 | err = errno; |
| 685 | goto ret; |
| 686 | } |
| 687 | } else { |
| 688 | /* |
| 689 | * If we _don't_ get EWOULDBLOCK, the connect has completed |
| 690 | * and we should set the socket as connected and writable. |
| 691 | */ |
| 692 | sock->connected = 1; |
| 693 | sock->writable = 1; |
| 694 | } |
| 695 | |
| 696 | uxsel_tell(sock); |
| 697 | |
| 698 | ret: |
| 699 | |
| 700 | /* |
| 701 | * No matter what happened, put the socket back in the tree. |
| 702 | */ |
| 703 | add234(sktree, sock); |
| 704 | |
| 705 | if (err) |
| 706 | plug_log(sock->plug, 1, sock->addr, sock->port, strerror(err), err); |
| 707 | return err; |
| 708 | } |
| 709 | |
| 710 | Socket sk_new(SockAddr addr, int port, int privport, int oobinline, |
| 711 | int nodelay, int keepalive, Plug plug) |
| 712 | { |
| 713 | Actual_Socket ret; |
| 714 | int err; |
| 715 | |
| 716 | /* |
| 717 | * Create Socket structure. |
| 718 | */ |
| 719 | ret = snew(struct Socket_tag); |
| 720 | ret->fn = &tcp_fn_table; |
| 721 | ret->error = NULL; |
| 722 | ret->plug = plug; |
| 723 | bufchain_init(&ret->output_data); |
| 724 | ret->connected = 0; /* to start with */ |
| 725 | ret->writable = 0; /* to start with */ |
| 726 | ret->sending_oob = 0; |
| 727 | ret->frozen = 0; |
| 728 | ret->frozen_readable = 0; |
| 729 | ret->localhost_only = 0; /* unused, but best init anyway */ |
| 730 | ret->pending_error = 0; |
| 731 | ret->parent = ret->child = NULL; |
| 732 | ret->oobpending = FALSE; |
| 733 | ret->outgoingeof = EOF_NO; |
| 734 | ret->incomingeof = FALSE; |
| 735 | ret->listener = 0; |
| 736 | ret->addr = addr; |
| 737 | START_STEP(ret->addr, ret->step); |
| 738 | ret->s = -1; |
| 739 | ret->oobinline = oobinline; |
| 740 | ret->nodelay = nodelay; |
| 741 | ret->keepalive = keepalive; |
| 742 | ret->privport = privport; |
| 743 | ret->port = port; |
| 744 | |
| 745 | err = 0; |
| 746 | do { |
| 747 | err = try_connect(ret); |
| 748 | } while (err && sk_nextaddr(ret->addr, &ret->step)); |
| 749 | |
| 750 | if (err) |
| 751 | ret->error = strerror(err); |
| 752 | |
| 753 | return (Socket) ret; |
| 754 | } |
| 755 | |
| 756 | Socket sk_newlistener(char *srcaddr, int port, Plug plug, int local_host_only, int orig_address_family) |
| 757 | { |
| 758 | int s; |
| 759 | #ifndef NO_IPV6 |
| 760 | struct addrinfo hints, *ai; |
| 761 | char portstr[6]; |
| 762 | #endif |
| 763 | union sockaddr_union u; |
| 764 | union sockaddr_union *addr; |
| 765 | int addrlen; |
| 766 | Actual_Socket ret; |
| 767 | int retcode; |
| 768 | int address_family; |
| 769 | int on = 1; |
| 770 | |
| 771 | /* |
| 772 | * Create Socket structure. |
| 773 | */ |
| 774 | ret = snew(struct Socket_tag); |
| 775 | ret->fn = &tcp_fn_table; |
| 776 | ret->error = NULL; |
| 777 | ret->plug = plug; |
| 778 | bufchain_init(&ret->output_data); |
| 779 | ret->writable = 0; /* to start with */ |
| 780 | ret->sending_oob = 0; |
| 781 | ret->frozen = 0; |
| 782 | ret->frozen_readable = 0; |
| 783 | ret->localhost_only = local_host_only; |
| 784 | ret->pending_error = 0; |
| 785 | ret->parent = ret->child = NULL; |
| 786 | ret->oobpending = FALSE; |
| 787 | ret->outgoingeof = EOF_NO; |
| 788 | ret->incomingeof = FALSE; |
| 789 | ret->listener = 1; |
| 790 | ret->addr = NULL; |
| 791 | |
| 792 | /* |
| 793 | * Translate address_family from platform-independent constants |
| 794 | * into local reality. |
| 795 | */ |
| 796 | address_family = (orig_address_family == ADDRTYPE_IPV4 ? AF_INET : |
| 797 | #ifndef NO_IPV6 |
| 798 | orig_address_family == ADDRTYPE_IPV6 ? AF_INET6 : |
| 799 | #endif |
| 800 | AF_UNSPEC); |
| 801 | |
| 802 | #ifndef NO_IPV6 |
| 803 | /* Let's default to IPv6. |
| 804 | * If the stack doesn't support IPv6, we will fall back to IPv4. */ |
| 805 | if (address_family == AF_UNSPEC) address_family = AF_INET6; |
| 806 | #else |
| 807 | /* No other choice, default to IPv4 */ |
| 808 | if (address_family == AF_UNSPEC) address_family = AF_INET; |
| 809 | #endif |
| 810 | |
| 811 | /* |
| 812 | * Open socket. |
| 813 | */ |
| 814 | s = socket(address_family, SOCK_STREAM, 0); |
| 815 | |
| 816 | #ifndef NO_IPV6 |
| 817 | /* If the host doesn't support IPv6 try fallback to IPv4. */ |
| 818 | if (s < 0 && address_family == AF_INET6) { |
| 819 | address_family = AF_INET; |
| 820 | s = socket(address_family, SOCK_STREAM, 0); |
| 821 | } |
| 822 | #endif |
| 823 | |
| 824 | if (s < 0) { |
| 825 | ret->error = strerror(errno); |
| 826 | return (Socket) ret; |
| 827 | } |
| 828 | |
| 829 | cloexec(s); |
| 830 | |
| 831 | ret->oobinline = 0; |
| 832 | |
| 833 | setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (const char *)&on, sizeof(on)); |
| 834 | |
| 835 | retcode = -1; |
| 836 | addr = NULL; addrlen = -1; /* placate optimiser */ |
| 837 | |
| 838 | if (srcaddr != NULL) { |
| 839 | #ifndef NO_IPV6 |
| 840 | hints.ai_flags = AI_NUMERICHOST; |
| 841 | hints.ai_family = address_family; |
| 842 | hints.ai_socktype = SOCK_STREAM; |
| 843 | hints.ai_protocol = 0; |
| 844 | hints.ai_addrlen = 0; |
| 845 | hints.ai_addr = NULL; |
| 846 | hints.ai_canonname = NULL; |
| 847 | hints.ai_next = NULL; |
| 848 | assert(port >= 0 && port <= 99999); |
| 849 | sprintf(portstr, "%d", port); |
| 850 | retcode = getaddrinfo(srcaddr, portstr, &hints, &ai); |
| 851 | if (retcode == 0) { |
| 852 | addr = (union sockaddr_union *)ai->ai_addr; |
| 853 | addrlen = ai->ai_addrlen; |
| 854 | } |
| 855 | #else |
| 856 | memset(&u,'\0',sizeof u); |
| 857 | u.sin.sin_family = AF_INET; |
| 858 | u.sin.sin_port = htons(port); |
| 859 | u.sin.sin_addr.s_addr = inet_addr(srcaddr); |
| 860 | if (u.sin.sin_addr.s_addr != (in_addr_t)(-1)) { |
| 861 | /* Override localhost_only with specified listen addr. */ |
| 862 | ret->localhost_only = ipv4_is_loopback(u.sin.sin_addr); |
| 863 | } |
| 864 | addr = &u; |
| 865 | addrlen = sizeof(u.sin); |
| 866 | retcode = 0; |
| 867 | #endif |
| 868 | } |
| 869 | |
| 870 | if (retcode != 0) { |
| 871 | memset(&u,'\0',sizeof u); |
| 872 | #ifndef NO_IPV6 |
| 873 | if (address_family == AF_INET6) { |
| 874 | u.sin6.sin6_family = AF_INET6; |
| 875 | u.sin6.sin6_port = htons(port); |
| 876 | if (local_host_only) |
| 877 | u.sin6.sin6_addr = in6addr_loopback; |
| 878 | else |
| 879 | u.sin6.sin6_addr = in6addr_any; |
| 880 | addr = &u; |
| 881 | addrlen = sizeof(u.sin6); |
| 882 | } else |
| 883 | #endif |
| 884 | { |
| 885 | u.sin.sin_family = AF_INET; |
| 886 | u.sin.sin_port = htons(port); |
| 887 | if (local_host_only) |
| 888 | u.sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK); |
| 889 | else |
| 890 | u.sin.sin_addr.s_addr = htonl(INADDR_ANY); |
| 891 | addr = &u; |
| 892 | addrlen = sizeof(u.sin); |
| 893 | } |
| 894 | } |
| 895 | |
| 896 | retcode = bind(s, &addr->sa, addrlen); |
| 897 | if (retcode < 0) { |
| 898 | close(s); |
| 899 | ret->error = strerror(errno); |
| 900 | return (Socket) ret; |
| 901 | } |
| 902 | |
| 903 | if (listen(s, SOMAXCONN) < 0) { |
| 904 | close(s); |
| 905 | ret->error = strerror(errno); |
| 906 | return (Socket) ret; |
| 907 | } |
| 908 | |
| 909 | #ifndef NO_IPV6 |
| 910 | /* |
| 911 | * If we were given ADDRTYPE_UNSPEC, we must also create an |
| 912 | * IPv4 listening socket and link it to this one. |
| 913 | */ |
| 914 | if (address_family == AF_INET6 && orig_address_family == ADDRTYPE_UNSPEC) { |
| 915 | Actual_Socket other; |
| 916 | |
| 917 | other = (Actual_Socket) sk_newlistener(srcaddr, port, plug, |
| 918 | local_host_only, ADDRTYPE_IPV4); |
| 919 | |
| 920 | if (other) { |
| 921 | if (!other->error) { |
| 922 | other->parent = ret; |
| 923 | ret->child = other; |
| 924 | } else { |
| 925 | /* If we couldn't create a listening socket on IPv4 as well |
| 926 | * as IPv6, we must return an error overall. */ |
| 927 | close(s); |
| 928 | sfree(ret); |
| 929 | return (Socket) other; |
| 930 | } |
| 931 | } |
| 932 | } |
| 933 | #endif |
| 934 | |
| 935 | ret->s = s; |
| 936 | |
| 937 | uxsel_tell(ret); |
| 938 | add234(sktree, ret); |
| 939 | |
| 940 | return (Socket) ret; |
| 941 | } |
| 942 | |
| 943 | static void sk_tcp_close(Socket sock) |
| 944 | { |
| 945 | Actual_Socket s = (Actual_Socket) sock; |
| 946 | |
| 947 | if (s->child) |
| 948 | sk_tcp_close((Socket)s->child); |
| 949 | |
| 950 | uxsel_del(s->s); |
| 951 | del234(sktree, s); |
| 952 | close(s->s); |
| 953 | if (s->addr) |
| 954 | sk_addr_free(s->addr); |
| 955 | sfree(s); |
| 956 | } |
| 957 | |
| 958 | void *sk_getxdmdata(void *sock, int *lenp) |
| 959 | { |
| 960 | Actual_Socket s = (Actual_Socket) sock; |
| 961 | union sockaddr_union u; |
| 962 | socklen_t addrlen; |
| 963 | char *buf; |
| 964 | static unsigned int unix_addr = 0xFFFFFFFF; |
| 965 | |
| 966 | /* |
| 967 | * We must check that this socket really _is_ an Actual_Socket. |
| 968 | */ |
| 969 | if (s->fn != &tcp_fn_table) |
| 970 | return NULL; /* failure */ |
| 971 | |
| 972 | addrlen = sizeof(u); |
| 973 | if (getsockname(s->s, &u.sa, &addrlen) < 0) |
| 974 | return NULL; |
| 975 | switch(u.sa.sa_family) { |
| 976 | case AF_INET: |
| 977 | *lenp = 6; |
| 978 | buf = snewn(*lenp, char); |
| 979 | PUT_32BIT_MSB_FIRST(buf, ntohl(u.sin.sin_addr.s_addr)); |
| 980 | PUT_16BIT_MSB_FIRST(buf+4, ntohs(u.sin.sin_port)); |
| 981 | break; |
| 982 | #ifndef NO_IPV6 |
| 983 | case AF_INET6: |
| 984 | *lenp = 6; |
| 985 | buf = snewn(*lenp, char); |
| 986 | if (IN6_IS_ADDR_V4MAPPED(&u.sin6.sin6_addr)) { |
| 987 | memcpy(buf, u.sin6.sin6_addr.s6_addr + 12, 4); |
| 988 | PUT_16BIT_MSB_FIRST(buf+4, ntohs(u.sin6.sin6_port)); |
| 989 | } else |
| 990 | /* This is stupid, but it's what XLib does. */ |
| 991 | memset(buf, 0, 6); |
| 992 | break; |
| 993 | #endif |
| 994 | case AF_UNIX: |
| 995 | *lenp = 6; |
| 996 | buf = snewn(*lenp, char); |
| 997 | PUT_32BIT_MSB_FIRST(buf, unix_addr--); |
| 998 | PUT_16BIT_MSB_FIRST(buf+4, getpid()); |
| 999 | break; |
| 1000 | |
| 1001 | /* XXX IPV6 */ |
| 1002 | |
| 1003 | default: |
| 1004 | return NULL; |
| 1005 | } |
| 1006 | |
| 1007 | return buf; |
| 1008 | } |
| 1009 | |
| 1010 | /* |
| 1011 | * The function which tries to send on a socket once it's deemed |
| 1012 | * writable. |
| 1013 | */ |
| 1014 | void try_send(Actual_Socket s) |
| 1015 | { |
| 1016 | while (s->sending_oob || bufchain_size(&s->output_data) > 0) { |
| 1017 | int nsent; |
| 1018 | int err; |
| 1019 | void *data; |
| 1020 | int len, urgentflag; |
| 1021 | |
| 1022 | if (s->sending_oob) { |
| 1023 | urgentflag = MSG_OOB; |
| 1024 | len = s->sending_oob; |
| 1025 | data = &s->oobdata; |
| 1026 | } else { |
| 1027 | urgentflag = 0; |
| 1028 | bufchain_prefix(&s->output_data, &data, &len); |
| 1029 | } |
| 1030 | nsent = send(s->s, data, len, urgentflag); |
| 1031 | noise_ultralight(nsent); |
| 1032 | if (nsent <= 0) { |
| 1033 | err = (nsent < 0 ? errno : 0); |
| 1034 | if (err == EWOULDBLOCK) { |
| 1035 | /* |
| 1036 | * Perfectly normal: we've sent all we can for the moment. |
| 1037 | */ |
| 1038 | s->writable = FALSE; |
| 1039 | return; |
| 1040 | } else { |
| 1041 | /* |
| 1042 | * We unfortunately can't just call plug_closing(), |
| 1043 | * because it's quite likely that we're currently |
| 1044 | * _in_ a call from the code we'd be calling back |
| 1045 | * to, so we'd have to make half the SSH code |
| 1046 | * reentrant. Instead we flag a pending error on |
| 1047 | * the socket, to be dealt with (by calling |
| 1048 | * plug_closing()) at some suitable future moment. |
| 1049 | */ |
| 1050 | s->pending_error = err; |
| 1051 | return; |
| 1052 | } |
| 1053 | } else { |
| 1054 | if (s->sending_oob) { |
| 1055 | if (nsent < len) { |
| 1056 | memmove(s->oobdata, s->oobdata+nsent, len-nsent); |
| 1057 | s->sending_oob = len - nsent; |
| 1058 | } else { |
| 1059 | s->sending_oob = 0; |
| 1060 | } |
| 1061 | } else { |
| 1062 | bufchain_consume(&s->output_data, nsent); |
| 1063 | } |
| 1064 | } |
| 1065 | } |
| 1066 | |
| 1067 | /* |
| 1068 | * If we reach here, we've finished sending everything we might |
| 1069 | * have needed to send. Send EOF, if we need to. |
| 1070 | */ |
| 1071 | if (s->outgoingeof == EOF_PENDING) { |
| 1072 | shutdown(s->s, SHUT_WR); |
| 1073 | s->outgoingeof = EOF_SENT; |
| 1074 | } |
| 1075 | |
| 1076 | /* |
| 1077 | * Also update the select status, because we don't need to select |
| 1078 | * for writing any more. |
| 1079 | */ |
| 1080 | uxsel_tell(s); |
| 1081 | } |
| 1082 | |
| 1083 | static int sk_tcp_write(Socket sock, const char *buf, int len) |
| 1084 | { |
| 1085 | Actual_Socket s = (Actual_Socket) sock; |
| 1086 | |
| 1087 | assert(s->outgoingeof == EOF_NO); |
| 1088 | |
| 1089 | /* |
| 1090 | * Add the data to the buffer list on the socket. |
| 1091 | */ |
| 1092 | bufchain_add(&s->output_data, buf, len); |
| 1093 | |
| 1094 | /* |
| 1095 | * Now try sending from the start of the buffer list. |
| 1096 | */ |
| 1097 | if (s->writable) |
| 1098 | try_send(s); |
| 1099 | |
| 1100 | /* |
| 1101 | * Update the select() status to correctly reflect whether or |
| 1102 | * not we should be selecting for write. |
| 1103 | */ |
| 1104 | uxsel_tell(s); |
| 1105 | |
| 1106 | return bufchain_size(&s->output_data); |
| 1107 | } |
| 1108 | |
| 1109 | static int sk_tcp_write_oob(Socket sock, const char *buf, int len) |
| 1110 | { |
| 1111 | Actual_Socket s = (Actual_Socket) sock; |
| 1112 | |
| 1113 | assert(s->outgoingeof == EOF_NO); |
| 1114 | |
| 1115 | /* |
| 1116 | * Replace the buffer list on the socket with the data. |
| 1117 | */ |
| 1118 | bufchain_clear(&s->output_data); |
| 1119 | assert(len <= sizeof(s->oobdata)); |
| 1120 | memcpy(s->oobdata, buf, len); |
| 1121 | s->sending_oob = len; |
| 1122 | |
| 1123 | /* |
| 1124 | * Now try sending from the start of the buffer list. |
| 1125 | */ |
| 1126 | if (s->writable) |
| 1127 | try_send(s); |
| 1128 | |
| 1129 | /* |
| 1130 | * Update the select() status to correctly reflect whether or |
| 1131 | * not we should be selecting for write. |
| 1132 | */ |
| 1133 | uxsel_tell(s); |
| 1134 | |
| 1135 | return s->sending_oob; |
| 1136 | } |
| 1137 | |
| 1138 | static void sk_tcp_write_eof(Socket sock) |
| 1139 | { |
| 1140 | Actual_Socket s = (Actual_Socket) sock; |
| 1141 | |
| 1142 | assert(s->outgoingeof == EOF_NO); |
| 1143 | |
| 1144 | /* |
| 1145 | * Mark the socket as pending outgoing EOF. |
| 1146 | */ |
| 1147 | s->outgoingeof = EOF_PENDING; |
| 1148 | |
| 1149 | /* |
| 1150 | * Now try sending from the start of the buffer list. |
| 1151 | */ |
| 1152 | if (s->writable) |
| 1153 | try_send(s); |
| 1154 | |
| 1155 | /* |
| 1156 | * Update the select() status to correctly reflect whether or |
| 1157 | * not we should be selecting for write. |
| 1158 | */ |
| 1159 | uxsel_tell(s); |
| 1160 | } |
| 1161 | |
| 1162 | static int net_select_result(int fd, int event) |
| 1163 | { |
| 1164 | int ret; |
| 1165 | char buf[20480]; /* nice big buffer for plenty of speed */ |
| 1166 | Actual_Socket s; |
| 1167 | u_long atmark; |
| 1168 | |
| 1169 | /* Find the Socket structure */ |
| 1170 | s = find234(sktree, &fd, cmpforsearch); |
| 1171 | if (!s) |
| 1172 | return 1; /* boggle */ |
| 1173 | |
| 1174 | noise_ultralight(event); |
| 1175 | |
| 1176 | switch (event) { |
| 1177 | case 4: /* exceptional */ |
| 1178 | if (!s->oobinline) { |
| 1179 | /* |
| 1180 | * On a non-oobinline socket, this indicates that we |
| 1181 | * can immediately perform an OOB read and get back OOB |
| 1182 | * data, which we will send to the back end with |
| 1183 | * type==2 (urgent data). |
| 1184 | */ |
| 1185 | ret = recv(s->s, buf, sizeof(buf), MSG_OOB); |
| 1186 | noise_ultralight(ret); |
| 1187 | if (ret <= 0) { |
| 1188 | return plug_closing(s->plug, |
| 1189 | ret == 0 ? "Internal networking trouble" : |
| 1190 | strerror(errno), errno, 0); |
| 1191 | } else { |
| 1192 | /* |
| 1193 | * Receiving actual data on a socket means we can |
| 1194 | * stop falling back through the candidate |
| 1195 | * addresses to connect to. |
| 1196 | */ |
| 1197 | if (s->addr) { |
| 1198 | sk_addr_free(s->addr); |
| 1199 | s->addr = NULL; |
| 1200 | } |
| 1201 | return plug_receive(s->plug, 2, buf, ret); |
| 1202 | } |
| 1203 | break; |
| 1204 | } |
| 1205 | |
| 1206 | /* |
| 1207 | * If we reach here, this is an oobinline socket, which |
| 1208 | * means we should set s->oobpending and then deal with it |
| 1209 | * when we get called for the readability event (which |
| 1210 | * should also occur). |
| 1211 | */ |
| 1212 | s->oobpending = TRUE; |
| 1213 | break; |
| 1214 | case 1: /* readable; also acceptance */ |
| 1215 | if (s->listener) { |
| 1216 | /* |
| 1217 | * On a listening socket, the readability event means a |
| 1218 | * connection is ready to be accepted. |
| 1219 | */ |
| 1220 | union sockaddr_union su; |
| 1221 | socklen_t addrlen = sizeof(su); |
| 1222 | int t; /* socket of connection */ |
| 1223 | int fl; |
| 1224 | |
| 1225 | memset(&su, 0, addrlen); |
| 1226 | t = accept(s->s, &su.sa, &addrlen); |
| 1227 | if (t < 0) { |
| 1228 | break; |
| 1229 | } |
| 1230 | |
| 1231 | fl = fcntl(t, F_GETFL); |
| 1232 | if (fl != -1) |
| 1233 | fcntl(t, F_SETFL, fl | O_NONBLOCK); |
| 1234 | |
| 1235 | if (s->localhost_only && |
| 1236 | !sockaddr_is_loopback(&su.sa)) { |
| 1237 | close(t); /* someone let nonlocal through?! */ |
| 1238 | } else if (plug_accepting(s->plug, t)) { |
| 1239 | close(t); /* denied or error */ |
| 1240 | } |
| 1241 | break; |
| 1242 | } |
| 1243 | |
| 1244 | /* |
| 1245 | * If we reach here, this is not a listening socket, so |
| 1246 | * readability really means readability. |
| 1247 | */ |
| 1248 | |
| 1249 | /* In the case the socket is still frozen, we don't even bother */ |
| 1250 | if (s->frozen) { |
| 1251 | s->frozen_readable = 1; |
| 1252 | break; |
| 1253 | } |
| 1254 | |
| 1255 | /* |
| 1256 | * We have received data on the socket. For an oobinline |
| 1257 | * socket, this might be data _before_ an urgent pointer, |
| 1258 | * in which case we send it to the back end with type==1 |
| 1259 | * (data prior to urgent). |
| 1260 | */ |
| 1261 | if (s->oobinline && s->oobpending) { |
| 1262 | atmark = 1; |
| 1263 | if (ioctl(s->s, SIOCATMARK, &atmark) == 0 && atmark) |
| 1264 | s->oobpending = FALSE; /* clear this indicator */ |
| 1265 | } else |
| 1266 | atmark = 1; |
| 1267 | |
| 1268 | ret = recv(s->s, buf, s->oobpending ? 1 : sizeof(buf), 0); |
| 1269 | noise_ultralight(ret); |
| 1270 | if (ret < 0) { |
| 1271 | if (errno == EWOULDBLOCK) { |
| 1272 | break; |
| 1273 | } |
| 1274 | } |
| 1275 | if (ret < 0) { |
| 1276 | /* |
| 1277 | * An error at this point _might_ be an error reported |
| 1278 | * by a non-blocking connect(). So before we return a |
| 1279 | * panic status to the user, let's just see whether |
| 1280 | * that's the case. |
| 1281 | */ |
| 1282 | int err = errno; |
| 1283 | if (s->addr) { |
| 1284 | plug_log(s->plug, 1, s->addr, s->port, strerror(err), err); |
| 1285 | while (s->addr && sk_nextaddr(s->addr, &s->step)) { |
| 1286 | err = try_connect(s); |
| 1287 | } |
| 1288 | } |
| 1289 | if (err != 0) |
| 1290 | return plug_closing(s->plug, strerror(err), err, 0); |
| 1291 | } else if (0 == ret) { |
| 1292 | s->incomingeof = TRUE; /* stop trying to read now */ |
| 1293 | uxsel_tell(s); |
| 1294 | return plug_closing(s->plug, NULL, 0, 0); |
| 1295 | } else { |
| 1296 | /* |
| 1297 | * Receiving actual data on a socket means we can |
| 1298 | * stop falling back through the candidate |
| 1299 | * addresses to connect to. |
| 1300 | */ |
| 1301 | if (s->addr) { |
| 1302 | sk_addr_free(s->addr); |
| 1303 | s->addr = NULL; |
| 1304 | } |
| 1305 | return plug_receive(s->plug, atmark ? 0 : 1, buf, ret); |
| 1306 | } |
| 1307 | break; |
| 1308 | case 2: /* writable */ |
| 1309 | if (!s->connected) { |
| 1310 | /* |
| 1311 | * select() reports a socket as _writable_ when an |
| 1312 | * asynchronous connection is completed. |
| 1313 | */ |
| 1314 | s->connected = s->writable = 1; |
| 1315 | uxsel_tell(s); |
| 1316 | break; |
| 1317 | } else { |
| 1318 | int bufsize_before, bufsize_after; |
| 1319 | s->writable = 1; |
| 1320 | bufsize_before = s->sending_oob + bufchain_size(&s->output_data); |
| 1321 | try_send(s); |
| 1322 | bufsize_after = s->sending_oob + bufchain_size(&s->output_data); |
| 1323 | if (bufsize_after < bufsize_before) |
| 1324 | plug_sent(s->plug, bufsize_after); |
| 1325 | } |
| 1326 | break; |
| 1327 | } |
| 1328 | |
| 1329 | return 1; |
| 1330 | } |
| 1331 | |
| 1332 | /* |
| 1333 | * Deal with socket errors detected in try_send(). |
| 1334 | */ |
| 1335 | void net_pending_errors(void) |
| 1336 | { |
| 1337 | int i; |
| 1338 | Actual_Socket s; |
| 1339 | |
| 1340 | /* |
| 1341 | * This might be a fiddly business, because it's just possible |
| 1342 | * that handling a pending error on one socket might cause |
| 1343 | * others to be closed. (I can't think of any reason this might |
| 1344 | * happen in current SSH implementation, but to maintain |
| 1345 | * generality of this network layer I'll assume the worst.) |
| 1346 | * |
| 1347 | * So what we'll do is search the socket list for _one_ socket |
| 1348 | * with a pending error, and then handle it, and then search |
| 1349 | * the list again _from the beginning_. Repeat until we make a |
| 1350 | * pass with no socket errors present. That way we are |
| 1351 | * protected against the socket list changing under our feet. |
| 1352 | */ |
| 1353 | |
| 1354 | do { |
| 1355 | for (i = 0; (s = index234(sktree, i)) != NULL; i++) { |
| 1356 | if (s->pending_error) { |
| 1357 | /* |
| 1358 | * An error has occurred on this socket. Pass it to the |
| 1359 | * plug. |
| 1360 | */ |
| 1361 | plug_closing(s->plug, strerror(s->pending_error), |
| 1362 | s->pending_error, 0); |
| 1363 | break; |
| 1364 | } |
| 1365 | } |
| 1366 | } while (s); |
| 1367 | } |
| 1368 | |
| 1369 | /* |
| 1370 | * Each socket abstraction contains a `void *' private field in |
| 1371 | * which the client can keep state. |
| 1372 | */ |
| 1373 | static void sk_tcp_set_private_ptr(Socket sock, void *ptr) |
| 1374 | { |
| 1375 | Actual_Socket s = (Actual_Socket) sock; |
| 1376 | s->private_ptr = ptr; |
| 1377 | } |
| 1378 | |
| 1379 | static void *sk_tcp_get_private_ptr(Socket sock) |
| 1380 | { |
| 1381 | Actual_Socket s = (Actual_Socket) sock; |
| 1382 | return s->private_ptr; |
| 1383 | } |
| 1384 | |
| 1385 | /* |
| 1386 | * Special error values are returned from sk_namelookup and sk_new |
| 1387 | * if there's a problem. These functions extract an error message, |
| 1388 | * or return NULL if there's no problem. |
| 1389 | */ |
| 1390 | const char *sk_addr_error(SockAddr addr) |
| 1391 | { |
| 1392 | return addr->error; |
| 1393 | } |
| 1394 | static const char *sk_tcp_socket_error(Socket sock) |
| 1395 | { |
| 1396 | Actual_Socket s = (Actual_Socket) sock; |
| 1397 | return s->error; |
| 1398 | } |
| 1399 | |
| 1400 | static void sk_tcp_set_frozen(Socket sock, int is_frozen) |
| 1401 | { |
| 1402 | Actual_Socket s = (Actual_Socket) sock; |
| 1403 | if (s->frozen == is_frozen) |
| 1404 | return; |
| 1405 | s->frozen = is_frozen; |
| 1406 | if (!is_frozen && s->frozen_readable) { |
| 1407 | char c; |
| 1408 | recv(s->s, &c, 1, MSG_PEEK); |
| 1409 | } |
| 1410 | s->frozen_readable = 0; |
| 1411 | uxsel_tell(s); |
| 1412 | } |
| 1413 | |
| 1414 | static void uxsel_tell(Actual_Socket s) |
| 1415 | { |
| 1416 | int rwx = 0; |
| 1417 | if (s->listener) { |
| 1418 | rwx |= 1; /* read == accept */ |
| 1419 | } else { |
| 1420 | if (!s->connected) |
| 1421 | rwx |= 2; /* write == connect */ |
| 1422 | if (s->connected && !s->frozen && !s->incomingeof) |
| 1423 | rwx |= 1 | 4; /* read, except */ |
| 1424 | if (bufchain_size(&s->output_data)) |
| 1425 | rwx |= 2; /* write */ |
| 1426 | } |
| 1427 | uxsel_set(s->s, rwx, net_select_result); |
| 1428 | } |
| 1429 | |
| 1430 | int net_service_lookup(char *service) |
| 1431 | { |
| 1432 | struct servent *se; |
| 1433 | se = getservbyname(service, NULL); |
| 1434 | if (se != NULL) |
| 1435 | return ntohs(se->s_port); |
| 1436 | else |
| 1437 | return 0; |
| 1438 | } |
| 1439 | |
| 1440 | char *get_hostname(void) |
| 1441 | { |
| 1442 | int len = 128; |
| 1443 | char *hostname = NULL; |
| 1444 | do { |
| 1445 | len *= 2; |
| 1446 | hostname = sresize(hostname, len, char); |
| 1447 | if ((gethostname(hostname, len) < 0) && |
| 1448 | (errno != ENAMETOOLONG)) { |
| 1449 | sfree(hostname); |
| 1450 | hostname = NULL; |
| 1451 | break; |
| 1452 | } |
| 1453 | } while (strlen(hostname) >= len-1); |
| 1454 | return hostname; |
| 1455 | } |
| 1456 | |
| 1457 | SockAddr platform_get_x11_unix_address(const char *sockpath, int displaynum) |
| 1458 | { |
| 1459 | SockAddr ret = snew(struct SockAddr_tag); |
| 1460 | int n; |
| 1461 | |
| 1462 | memset(ret, 0, sizeof *ret); |
| 1463 | ret->superfamily = UNIX; |
| 1464 | /* |
| 1465 | * In special circumstances (notably Mac OS X Leopard), we'll |
| 1466 | * have been passed an explicit Unix socket path. |
| 1467 | */ |
| 1468 | if (sockpath) { |
| 1469 | n = snprintf(ret->hostname, sizeof ret->hostname, |
| 1470 | "%s", sockpath); |
| 1471 | } else { |
| 1472 | n = snprintf(ret->hostname, sizeof ret->hostname, |
| 1473 | "%s%d", X11_UNIX_PATH, displaynum); |
| 1474 | } |
| 1475 | |
| 1476 | if (n < 0) |
| 1477 | ret->error = "snprintf failed"; |
| 1478 | else if (n >= sizeof ret->hostname) |
| 1479 | ret->error = "X11 UNIX name too long"; |
| 1480 | |
| 1481 | #ifndef NO_IPV6 |
| 1482 | ret->ais = NULL; |
| 1483 | #else |
| 1484 | ret->addresses = NULL; |
| 1485 | ret->naddresses = 0; |
| 1486 | #endif |
| 1487 | ret->refcount = 1; |
| 1488 | return ret; |
| 1489 | } |