qemu-sockets.c

   1 /*
   2  *  inet and unix socket functions for qemu
   3  *
   4  *  (c) 2008 Gerd Hoffmann <kraxel@redhat.com>
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; under version 2 of the License.
   9  *
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  */
  15 #include <stdio.h>
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include <ctype.h>
  19 #include <errno.h>
  20 #include <unistd.h>
  21
  22 #include "qemu_socket.h"
  23 #include "qemu-common.h" /* for qemu_isdigit */
  24
  25 #ifndef AI_ADDRCONFIG
  26 # define AI_ADDRCONFIG 0
  27 #endif
  28
  29 static int sockets_debug = 0;
  30 static const int on=1, off=0;
  31
  32 /* used temporarely until all users are converted to QemuOpts */
  33 QemuOptsList dummy_opts = {
  34     .name = "dummy",
  35     .head = TAILQ_HEAD_INITIALIZER(dummy_opts.head),
  36     .desc = {
  37         {
  38             .name = "path",
  39             .type = QEMU_OPT_STRING,
  40         },{
  41             .name = "host",
  42             .type = QEMU_OPT_STRING,
  43         },{
  44             .name = "port",
  45             .type = QEMU_OPT_STRING,
  46         },{
  47             .name = "to",
  48             .type = QEMU_OPT_NUMBER,
  49         },{
  50             .name = "ipv4",
  51             .type = QEMU_OPT_BOOL,
  52         },{
  53             .name = "ipv6",
  54             .type = QEMU_OPT_BOOL,
  55         },
  56         { /* end if list */ }
  57     },
  58 };
  59
  60 static int inet_getport(struct addrinfo *e)
  61 {
  62     struct sockaddr_in *i4;
  63     struct sockaddr_in6 *i6;
  64
  65     switch (e->ai_family) {
  66     case PF_INET6:
  67         i6 = (void*)e->ai_addr;
  68         return ntohs(i6->sin6_port);
  69     case PF_INET:
  70         i4 = (void*)e->ai_addr;
  71         return ntohs(i4->sin_port);
  72     default:
  73         return 0;
  74     }
  75 }
  76
  77 static void inet_setport(struct addrinfo *e, int port)
  78 {
  79     struct sockaddr_in *i4;
  80     struct sockaddr_in6 *i6;
  81
  82     switch (e->ai_family) {
  83     case PF_INET6:
  84         i6 = (void*)e->ai_addr;
  85         i6->sin6_port = htons(port);
  86         break;
  87     case PF_INET:
  88         i4 = (void*)e->ai_addr;
  89         i4->sin_port = htons(port);
  90         break;
  91     }
  92 }
  93
  94 static const char *inet_strfamily(int family)
  95 {
  96     switch (family) {
  97     case PF_INET6: return "ipv6";
  98     case PF_INET:  return "ipv4";
  99     case PF_UNIX:  return "unix";
 100     }
 101     return "????";
 102 }
 103
 104 static void inet_print_addrinfo(const char *tag, struct addrinfo *res)
 105 {
 106     struct addrinfo *e;
 107     char uaddr[INET6_ADDRSTRLEN+1];
 108     char uport[33];
 109
 110     for (e = res; e != NULL; e = e->ai_next) {
 111         getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
 112                     uaddr,INET6_ADDRSTRLEN,uport,32,
 113                     NI_NUMERICHOST | NI_NUMERICSERV);
 114         fprintf(stderr,"%s: getaddrinfo: family %s, host %s, port %s\n",
 115                 tag, inet_strfamily(e->ai_family), uaddr, uport);
 116     }
 117 }
 118
 119 int inet_listen_opts(QemuOpts *opts, int port_offset)
 120 {
 121     struct addrinfo ai,*res,*e;
 122     const char *addr;
 123     char port[33];
 124     char uaddr[INET6_ADDRSTRLEN+1];
 125     char uport[33];
 126     int slisten,rc,to,try_next;
 127
 128     memset(&ai,0, sizeof(ai));
 129     ai.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
 130     ai.ai_family = PF_UNSPEC;
 131     ai.ai_socktype = SOCK_STREAM;
 132
 133     if (qemu_opt_get(opts, "port") == NULL) {
 134         fprintf(stderr, "%s: host and/or port not specified\n", __FUNCTION__);
 135         return -1;
 136     }
 137     pstrcpy(port, sizeof(port), qemu_opt_get(opts, "port"));
 138     addr = qemu_opt_get(opts, "host");
 139
 140     to = qemu_opt_get_number(opts, "to", 0);
 141     if (qemu_opt_get_bool(opts, "ipv4", 0))
 142         ai.ai_family = PF_INET;
 143     if (qemu_opt_get_bool(opts, "ipv6", 0))
 144         ai.ai_family = PF_INET6;
 145
 146     /* lookup */
 147     if (port_offset)
 148         snprintf(port, sizeof(port), "%d", atoi(port) + port_offset);
 149     rc = getaddrinfo(strlen(addr) ? addr : NULL, port, &ai, &res);
 150     if (rc != 0) {
 151         fprintf(stderr,"getaddrinfo(%s,%s): %s\n", addr, port,
 152                 gai_strerror(rc));
 153         return -1;
 154     }
 155     if (sockets_debug)
 156         inet_print_addrinfo(__FUNCTION__, res);
 157
 158     /* create socket + bind */
 159     for (e = res; e != NULL; e = e->ai_next) {
 160         getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
 161                         uaddr,INET6_ADDRSTRLEN,uport,32,
 162                         NI_NUMERICHOST | NI_NUMERICSERV);
 163         slisten = socket(e->ai_family, e->ai_socktype, e->ai_protocol);
 164         if (slisten < 0) {
 165             fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,
 166                     inet_strfamily(e->ai_family), strerror(errno));
 167             continue;
 168         }
 169
 170         setsockopt(slisten,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));
 171 #ifdef IPV6_V6ONLY
 172         if (e->ai_family == PF_INET6) {
 173             /* listen on both ipv4 and ipv6 */
 174             setsockopt(slisten,IPPROTO_IPV6,IPV6_V6ONLY,(void*)&off,
 175                 sizeof(off));
 176         }
 177 #endif
 178
 179         for (;;) {
 180             if (bind(slisten, e->ai_addr, e->ai_addrlen) == 0) {
 181                 if (sockets_debug)
 182                     fprintf(stderr,"%s: bind(%s,%s,%d): OK\n", __FUNCTION__,
 183                         inet_strfamily(e->ai_family), uaddr, inet_getport(e));
 184                 goto listen;
 185             }
 186             try_next = to && (inet_getport(e) <= to + port_offset);
 187             if (!try_next || sockets_debug)
 188                 fprintf(stderr,"%s: bind(%s,%s,%d): %s\n", __FUNCTION__,
 189                         inet_strfamily(e->ai_family), uaddr, inet_getport(e),
 190                         strerror(errno));
 191             if (try_next) {
 192                 inet_setport(e, inet_getport(e) + 1);
 193                 continue;
 194             }
 195             break;
 196         }
 197         closesocket(slisten);
 198     }
 199     fprintf(stderr, "%s: FAILED\n", __FUNCTION__);
 200     freeaddrinfo(res);
 201     return -1;
 202
 203 listen:
 204     if (listen(slisten,1) != 0) {
 205         perror("listen");
 206         closesocket(slisten);
 207         freeaddrinfo(res);
 208         return -1;
 209     }
 210     snprintf(uport, sizeof(uport), "%d", inet_getport(e) - port_offset);
 211     qemu_opt_set(opts, "host", uaddr);
 212     qemu_opt_set(opts, "port", uport);
 213     qemu_opt_set(opts, "ipv6", (e->ai_family == PF_INET6) ? "on" : "off");
 214     qemu_opt_set(opts, "ipv4", (e->ai_family != PF_INET6) ? "on" : "off");
 215     freeaddrinfo(res);
 216     return slisten;
 217 }
 218
 219 int inet_connect_opts(QemuOpts *opts)
 220 {
 221     struct addrinfo ai,*res,*e;
 222     const char *addr;
 223     const char *port;
 224     char uaddr[INET6_ADDRSTRLEN+1];
 225     char uport[33];
 226     int sock,rc;
 227
 228     memset(&ai,0, sizeof(ai));
 229     ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
 230     ai.ai_family = PF_UNSPEC;
 231     ai.ai_socktype = SOCK_STREAM;
 232
 233     addr = qemu_opt_get(opts, "host");
 234     port = qemu_opt_get(opts, "port");
 235     if (addr == NULL || port == NULL) {
 236         fprintf(stderr, "inet_connect: host and/or port not specified\n");
 237         return -1;
 238     }
 239
 240     if (qemu_opt_get_bool(opts, "ipv4", 0))
 241         ai.ai_family = PF_INET;
 242     if (qemu_opt_get_bool(opts, "ipv6", 0))
 243         ai.ai_family = PF_INET6;
 244
 245     /* lookup */
 246     if (0 != (rc = getaddrinfo(addr, port, &ai, &res))) {
 247         fprintf(stderr,"getaddrinfo(%s,%s): %s\n", addr, port,
 248                 gai_strerror(rc));
 249         return -1;
 250     }
 251     if (sockets_debug)
 252         inet_print_addrinfo(__FUNCTION__, res);
 253
 254     for (e = res; e != NULL; e = e->ai_next) {
 255         if (getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
 256                             uaddr,INET6_ADDRSTRLEN,uport,32,
 257                             NI_NUMERICHOST | NI_NUMERICSERV) != 0) {
 258             fprintf(stderr,"%s: getnameinfo: oops\n", __FUNCTION__);
 259             continue;
 260         }
 261         sock = socket(e->ai_family, e->ai_socktype, e->ai_protocol);
 262         if (sock < 0) {
 263             fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,
 264             inet_strfamily(e->ai_family), strerror(errno));
 265             continue;
 266         }
 267         setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));
 268
 269         /* connect to peer */
 270         if (connect(sock,e->ai_addr,e->ai_addrlen) < 0) {
 271             if (sockets_debug || NULL == e->ai_next)
 272                 fprintf(stderr, "%s: connect(%s,%s,%s,%s): %s\n", __FUNCTION__,
 273                         inet_strfamily(e->ai_family),
 274                         e->ai_canonname, uaddr, uport, strerror(errno));
 275             closesocket(sock);
 276             continue;
 277         }
 278         if (sockets_debug)
 279             fprintf(stderr, "%s: connect(%s,%s,%s,%s): OK\n", __FUNCTION__,
 280                     inet_strfamily(e->ai_family),
 281                     e->ai_canonname, uaddr, uport);
 282         freeaddrinfo(res);
 283         return sock;
 284     }
 285     freeaddrinfo(res);
 286     return -1;
 287 }
 288
 289 /* compatibility wrapper */
 290 static int inet_parse(QemuOpts *opts, const char *str)
 291 {
 292     const char *optstr, *h;
 293     char addr[64];
 294     char port[33];
 295     int pos;
 296
 297     /* parse address */
 298     if (str[0] == ':') {
 299         /* no host given */
 300         addr[0] = '\0';
 301         if (1 != sscanf(str,":%32[^,]%n",port,&pos)) {
 302             fprintf(stderr, "%s: portonly parse error (%s)\n",
 303                     __FUNCTION__, str);
 304             return -1;
 305         }
 306     } else if (str[0] == '[') {
 307         /* IPv6 addr */
 308         if (2 != sscanf(str,"[%64[^]]]:%32[^,]%n",addr,port,&pos)) {
 309             fprintf(stderr, "%s: ipv6 parse error (%s)\n",
 310                     __FUNCTION__, str);
 311             return -1;
 312         }
 313         qemu_opt_set(opts, "ipv6", "yes");
 314     } else if (qemu_isdigit(str[0])) {
 315         /* IPv4 addr */
 316         if (2 != sscanf(str,"%64[0-9.]:%32[^,]%n",addr,port,&pos)) {
 317             fprintf(stderr, "%s: ipv4 parse error (%s)\n",
 318                     __FUNCTION__, str);
 319             return -1;
 320         }
 321         qemu_opt_set(opts, "ipv4", "yes");
 322     } else {
 323         /* hostname */
 324         if (2 != sscanf(str,"%64[^:]:%32[^,]%n",addr,port,&pos)) {
 325             fprintf(stderr, "%s: hostname parse error (%s)\n",
 326                     __FUNCTION__, str);
 327             return -1;
 328         }
 329     }
 330     qemu_opt_set(opts, "host", addr);
 331     qemu_opt_set(opts, "port", port);
 332
 333     /* parse options */
 334     optstr = str + pos;
 335     h = strstr(optstr, ",to=");
 336     if (h)
 337         qemu_opt_set(opts, "to", h+4);
 338     if (strstr(optstr, ",ipv4"))
 339         qemu_opt_set(opts, "ipv4", "yes");
 340     if (strstr(optstr, ",ipv6"))
 341         qemu_opt_set(opts, "ipv6", "yes");
 342     return 0;
 343 }
 344
 345 int inet_listen(const char *str, char *ostr, int olen,
 346                 int socktype, int port_offset)
 347 {
 348     QemuOpts *opts;
 349     char *optstr;
 350     int sock = -1;
 351
 352     opts = qemu_opts_create(&dummy_opts, NULL, 0);
 353     if (inet_parse(opts, str) == 0) {
 354         sock = inet_listen_opts(opts, port_offset);
 355         if (sock != -1 && ostr) {
 356             optstr = strchr(str, ',');
 357             if (qemu_opt_get_bool(opts, "ipv6", 0)) {
 358                 snprintf(ostr, olen, "[%s]:%s%s",
 359                          qemu_opt_get(opts, "host"),
 360                          qemu_opt_get(opts, "port"),
 361                          optstr ? optstr : "");
 362             } else {
 363                 snprintf(ostr, olen, "%s:%s%s",
 364                          qemu_opt_get(opts, "host"),
 365                          qemu_opt_get(opts, "port"),
 366                          optstr ? optstr : "");
 367             }
 368         }
 369     }
 370     qemu_opts_del(opts);
 371     return sock;
 372 }
 373
 374 int inet_connect(const char *str, int socktype)
 375 {
 376     QemuOpts *opts;
 377     int sock = -1;
 378
 379     opts = qemu_opts_create(&dummy_opts, NULL, 0);
 380     if (inet_parse(opts, str) == 0)
 381         sock = inet_connect_opts(opts);
 382     qemu_opts_del(opts);
 383     return sock;
 384 }
 385
 386 #ifndef _WIN32
 387
 388 int unix_listen_opts(QemuOpts *opts)
 389 {
 390     struct sockaddr_un un;
 391     const char *path = qemu_opt_get(opts, "path");
 392     int sock, fd;
 393
 394     sock = socket(PF_UNIX, SOCK_STREAM, 0);
 395     if (sock < 0) {
 396         perror("socket(unix)");
 397         return -1;
 398     }
 399
 400     memset(&un, 0, sizeof(un));
 401     un.sun_family = AF_UNIX;
 402     if (path && strlen(path)) {
 403         snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
 404     } else {
 405         char *tmpdir = getenv("TMPDIR");
 406         snprintf(un.sun_path, sizeof(un.sun_path), "%s/qemu-socket-XXXXXX",
 407                  tmpdir ? tmpdir : "/tmp");
 408         /*
 409          * This dummy fd usage silences the mktemp() unsecure warning.
 410          * Using mkstemp() doesn't make things more secure here
 411          * though.  bind() complains about existing files, so we have
 412          * to unlink first and thus re-open the race window.  The
 413          * worst case possible is bind() failing, i.e. a DoS attack.
 414          */
 415         fd = mkstemp(un.sun_path); close(fd);
 416         qemu_opt_set(opts, "path", un.sun_path);
 417     }
 418
 419     unlink(un.sun_path);
 420     if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
 421         fprintf(stderr, "bind(unix:%s): %s\n", un.sun_path, strerror(errno));
 422         goto err;
 423     }
 424     if (listen(sock, 1) < 0) {
 425         fprintf(stderr, "listen(unix:%s): %s\n", un.sun_path, strerror(errno));
 426         goto err;
 427     }
 428
 429     if (sockets_debug)
 430         fprintf(stderr, "bind(unix:%s): OK\n", un.sun_path);
 431     return sock;
 432
 433 err:
 434     closesocket(sock);
 435     return -1;
 436 }
 437
 438 int unix_connect_opts(QemuOpts *opts)
 439 {
 440     struct sockaddr_un un;
 441     const char *path = qemu_opt_get(opts, "path");
 442     int sock;
 443
 444     if (NULL == path) {
 445         fprintf(stderr, "unix connect: no path specified\n");
 446         return -1;
 447     }
 448
 449     sock = socket(PF_UNIX, SOCK_STREAM, 0);
 450     if (sock < 0) {
 451         perror("socket(unix)");
 452         return -1;
 453     }
 454
 455     memset(&un, 0, sizeof(un));
 456     un.sun_family = AF_UNIX;
 457     snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
 458     if (connect(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
 459         fprintf(stderr, "connect(unix:%s): %s\n", path, strerror(errno));
 460         return -1;
 461     }
 462
 463     if (sockets_debug)
 464         fprintf(stderr, "connect(unix:%s): OK\n", path);
 465     return sock;
 466 }
 467
 468 /* compatibility wrapper */
 469 int unix_listen(const char *str, char *ostr, int olen)
 470 {
 471     QemuOpts *opts;
 472     char *path, *optstr;
 473     int sock, len;
 474
 475     opts = qemu_opts_create(&dummy_opts, NULL, 0);
 476
 477     optstr = strchr(str, ',');
 478     if (optstr) {
 479         len = optstr - str;
 480         if (len) {
 481             path = qemu_malloc(len+1);
 482             snprintf(path, len+1, "%.*s", len, str);
 483             qemu_opt_set(opts, "path", path);
 484             qemu_free(path);
 485         }
 486     } else {
 487         qemu_opt_set(opts, "path", str);
 488     }
 489
 490     sock = unix_listen_opts(opts);
 491
 492     if (sock != -1 && ostr)
 493         snprintf(ostr, olen, "%s%s", qemu_opt_get(opts, "path"), optstr ? optstr : "");
 494     qemu_opts_del(opts);
 495     return sock;
 496 }
 497
 498 int unix_connect(const char *path)
 499 {
 500     QemuOpts *opts;
 501     int sock;
 502
 503     opts = qemu_opts_create(&dummy_opts, NULL, 0);
 504     qemu_opt_set(opts, "path", path);
 505     sock = unix_connect_opts(opts);
 506     qemu_opts_del(opts);
 507     return sock;
 508 }
 509
 510 #else
 511
 512 int unix_listen_opts(QemuOpts *opts)
 513 {
 514     fprintf(stderr, "unix sockets are not available on windows\n");
 515     return -1;
 516 }
 517
 518 int unix_connect_opts(QemuOpts *opts)
 519 {
 520     fprintf(stderr, "unix sockets are not available on windows\n");
 521     return -1;
 522 }
 523
 524 int unix_listen(const char *path, char *ostr, int olen)
 525 {
 526     fprintf(stderr, "unix sockets are not available on windows\n");
 527     return -1;
 528 }
 529
 530 int unix_connect(const char *path)
 531 {
 532     fprintf(stderr, "unix sockets are not available on windows\n");
 533     return -1;
 534 }
 535
 536 #endif