qemu-sockets.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <ctype.h>
   5 #include <errno.h>
   6 #include <unistd.h>
   7
   8 #include "qemu_socket.h"
   9
  10 #ifndef AI_ADDRCONFIG
  11 # define AI_ADDRCONFIG 0
  12 #endif
  13
  14 static int sockets_debug = 0;
  15 static const int on=1, off=0;
  16
  17 static int inet_getport(struct addrinfo *e)
  18 {
  19     struct sockaddr_in *i4;
  20     struct sockaddr_in6 *i6;
  21
  22     switch (e->ai_family) {
  23     case PF_INET6:
  24         i6 = (void*)e->ai_addr;
  25         return ntohs(i6->sin6_port);
  26     case PF_INET:
  27         i4 = (void*)e->ai_addr;
  28         return ntohs(i4->sin_port);
  29     default:
  30         return 0;
  31     }
  32 }
  33
  34 static void inet_setport(struct addrinfo *e, int port)
  35 {
  36     struct sockaddr_in *i4;
  37     struct sockaddr_in6 *i6;
  38
  39     switch (e->ai_family) {
  40     case PF_INET6:
  41         i6 = (void*)e->ai_addr;
  42         i6->sin6_port = htons(port);
  43         break;
  44     case PF_INET:
  45         i4 = (void*)e->ai_addr;
  46         i4->sin_port = htons(port);
  47         break;
  48     }
  49 }
  50
  51 static const char *inet_strfamily(int family)
  52 {
  53     switch (family) {
  54     case PF_INET6: return "ipv6";
  55     case PF_INET:  return "ipv4";
  56     case PF_UNIX:  return "unix";
  57     }
  58     return "????";
  59 }
  60
  61 static void inet_print_addrinfo(const char *tag, struct addrinfo *res)
  62 {
  63     struct addrinfo *e;
  64     char uaddr[INET6_ADDRSTRLEN+1];
  65     char uport[33];
  66
  67     for (e = res; e != NULL; e = e->ai_next) {
  68         getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
  69                     uaddr,INET6_ADDRSTRLEN,uport,32,
  70                     NI_NUMERICHOST | NI_NUMERICSERV);
  71         fprintf(stderr,"%s: getaddrinfo: family %s, host %s, port %s\n",
  72                 tag, inet_strfamily(e->ai_family), uaddr, uport);
  73     }
  74 }
  75
  76 int inet_listen(const char *str, char *ostr, int olen,
  77                 int socktype, int port_offset)
  78 {
  79     struct addrinfo ai,*res,*e;
  80     char addr[64];
  81     char port[33];
  82     char uaddr[INET6_ADDRSTRLEN+1];
  83     char uport[33];
  84     const char *opts, *h;
  85     int slisten,rc,pos,to,try_next;
  86
  87     memset(&ai,0, sizeof(ai));
  88     ai.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
  89     ai.ai_family = PF_UNSPEC;
  90     ai.ai_socktype = socktype;
  91
  92     /* parse address */
  93     if (str[0] == ':') {
  94         /* no host given */
  95         strcpy(addr,"");
  96         if (1 != sscanf(str,":%32[^,]%n",port,&pos)) {
  97             fprintf(stderr, "%s: portonly parse error (%s)\n",
  98                     __FUNCTION__, str);
  99             return -1;
 100         }
 101     } else if (str[0] == '[') {
 102         /* IPv6 addr */
 103         if (2 != sscanf(str,"[%64[^]]]:%32[^,]%n",addr,port,&pos)) {
 104             fprintf(stderr, "%s: ipv6 parse error (%s)\n",
 105                     __FUNCTION__, str);
 106             return -1;
 107         }
 108         ai.ai_family = PF_INET6;
 109     } else if (isdigit(str[0])) {
 110         /* IPv4 addr */
 111         if (2 != sscanf(str,"%64[0-9.]:%32[^,]%n",addr,port,&pos)) {
 112             fprintf(stderr, "%s: ipv4 parse error (%s)\n",
 113                     __FUNCTION__, str);
 114             return -1;
 115         }
 116         ai.ai_family = PF_INET;
 117     } else {
 118         /* hostname */
 119         if (2 != sscanf(str,"%64[^:]:%32[^,]%n",addr,port,&pos)) {
 120             fprintf(stderr, "%s: hostname parse error (%s)\n",
 121                     __FUNCTION__, str);
 122             return -1;
 123         }
 124     }
 125
 126     /* parse options */
 127     opts = str + pos;
 128     h = strstr(opts, ",to=");
 129     to = h ? atoi(h+4) : 0;
 130     if (strstr(opts, ",ipv4"))
 131         ai.ai_family = PF_INET;
 132     if (strstr(opts, ",ipv6"))
 133         ai.ai_family = PF_INET6;
 134
 135     /* lookup */
 136     if (port_offset)
 137         snprintf(port, sizeof(port), "%d", atoi(port) + port_offset);
 138     rc = getaddrinfo(strlen(addr) ? addr : NULL, port, &ai, &res);
 139     if (rc != 0) {
 140         fprintf(stderr,"%s: getaddrinfo(%s,%s): %s\n", __FUNCTION__,
 141                 addr, port, gai_strerror(rc));
 142         return -1;
 143     }
 144     if (sockets_debug)
 145         inet_print_addrinfo(__FUNCTION__, res);
 146
 147     /* create socket + bind */
 148     for (e = res; e != NULL; e = e->ai_next) {
 149         getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
 150                     uaddr,INET6_ADDRSTRLEN,uport,32,
 151                     NI_NUMERICHOST | NI_NUMERICSERV);
 152         slisten = socket(e->ai_family, e->ai_socktype, e->ai_protocol);
 153         if (slisten < 0) {
 154             fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,
 155                     inet_strfamily(e->ai_family), strerror(errno));
 156             continue;
 157         }
 158
 159         setsockopt(slisten,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));
 160 #ifdef IPV6_V6ONLY
 161         if (e->ai_family == PF_INET6) {
 162             /* listen on both ipv4 and ipv6 */
 163             setsockopt(slisten,IPPROTO_IPV6,IPV6_V6ONLY,(void*)&off,sizeof(off));
 164         }
 165 #endif
 166
 167         for (;;) {
 168             if (bind(slisten, e->ai_addr, e->ai_addrlen) == 0) {
 169                 if (sockets_debug)
 170                     fprintf(stderr,"%s: bind(%s,%s,%d): OK\n", __FUNCTION__,
 171                             inet_strfamily(e->ai_family), uaddr, inet_getport(e));
 172                 goto listen;
 173             }
 174             try_next = to && (inet_getport(e) <= to + port_offset);
 175             if (!try_next || sockets_debug)
 176                 fprintf(stderr,"%s: bind(%s,%s,%d): %s\n", __FUNCTION__,
 177                         inet_strfamily(e->ai_family), uaddr, inet_getport(e),
 178                         strerror(errno));
 179             if (try_next) {
 180                 inet_setport(e, inet_getport(e) + 1);
 181                 continue;
 182             }
 183             break;
 184         }
 185         closesocket(slisten);
 186     }
 187     fprintf(stderr, "%s: FAILED\n", __FUNCTION__);
 188     freeaddrinfo(res);
 189     return -1;
 190
 191 listen:
 192     if (listen(slisten,1) != 0) {
 193         perror("listen");
 194         closesocket(slisten);
 195         return -1;
 196     }
 197     if (ostr) {
 198         if (e->ai_family == PF_INET6) {
 199             snprintf(ostr, olen, "[%s]:%d%s", uaddr,
 200                      inet_getport(e) - port_offset, opts);
 201         } else {
 202             snprintf(ostr, olen, "%s:%d%s", uaddr,
 203                      inet_getport(e) - port_offset, opts);
 204         }
 205     }
 206     freeaddrinfo(res);
 207     return slisten;
 208 }
 209
 210 int inet_connect(const char *str, int socktype)
 211 {
 212     struct addrinfo ai,*res,*e;
 213     char addr[64];
 214     char port[33];
 215     char uaddr[INET6_ADDRSTRLEN+1];
 216     char uport[33];
 217     int sock,rc;
 218
 219     memset(&ai,0, sizeof(ai));
 220     ai.ai_flags = AI_CANONNAME | AI_ADDRCONFIG;
 221     ai.ai_family = PF_UNSPEC;
 222     ai.ai_socktype = socktype;
 223
 224     /* parse address */
 225     if (str[0] == '[') {
 226         /* IPv6 addr */
 227         if (2 != sscanf(str,"[%64[^]]]:%32[^,]",addr,port)) {
 228             fprintf(stderr, "%s: ipv6 parse error (%s)\n",
 229                     __FUNCTION__, str);
 230             return -1;
 231         }
 232         ai.ai_family = PF_INET6;
 233     } else if (isdigit(str[0])) {
 234         /* IPv4 addr */
 235         if (2 != sscanf(str,"%64[0-9.]:%32[^,]",addr,port)) {
 236             fprintf(stderr, "%s: ipv4 parse error (%s)\n",
 237                     __FUNCTION__, str);
 238             return -1;
 239         }
 240         ai.ai_family = PF_INET;
 241     } else {
 242         /* hostname */
 243         if (2 != sscanf(str,"%64[^:]:%32[^,]",addr,port)) {
 244             fprintf(stderr, "%s: hostname parse error (%s)\n",
 245                     __FUNCTION__, str);
 246             return -1;
 247         }
 248     }
 249
 250     /* parse options */
 251     if (strstr(str, ",ipv4"))
 252         ai.ai_family = PF_INET;
 253     if (strstr(str, ",ipv6"))
 254         ai.ai_family = PF_INET6;
 255
 256     /* lookup */
 257     if (0 != (rc = getaddrinfo(addr, port, &ai, &res))) {
 258         fprintf(stderr,"getaddrinfo(%s,%s): %s\n", gai_strerror(rc),
 259                 addr, port);
 260         return -1;
 261     }
 262     if (sockets_debug)
 263         inet_print_addrinfo(__FUNCTION__, res);
 264
 265     for (e = res; e != NULL; e = e->ai_next) {
 266         if (getnameinfo((struct sockaddr*)e->ai_addr,e->ai_addrlen,
 267                         uaddr,INET6_ADDRSTRLEN,uport,32,
 268                         NI_NUMERICHOST | NI_NUMERICSERV) != 0) {
 269             fprintf(stderr,"%s: getnameinfo: oops\n", __FUNCTION__);
 270             continue;
 271         }
 272         sock = socket(e->ai_family, e->ai_socktype, e->ai_protocol);
 273         if (sock < 0) {
 274             fprintf(stderr,"%s: socket(%s): %s\n", __FUNCTION__,
 275                     inet_strfamily(e->ai_family), strerror(errno));
 276             continue;
 277         }
 278         setsockopt(sock,SOL_SOCKET,SO_REUSEADDR,(void*)&on,sizeof(on));
 279
 280         /* connect to peer */
 281         if (connect(sock,e->ai_addr,e->ai_addrlen) < 0) {
 282             if (sockets_debug || NULL == e->ai_next)
 283                 fprintf(stderr, "%s: connect(%s,%s,%s,%s): %s\n", __FUNCTION__,
 284                         inet_strfamily(e->ai_family),
 285                         e->ai_canonname, uaddr, uport, strerror(errno));
 286             closesocket(sock);
 287             continue;
 288         }
 289         if (sockets_debug)
 290             fprintf(stderr, "%s: connect(%s,%s,%s,%s): OK\n", __FUNCTION__,
 291                     inet_strfamily(e->ai_family),
 292                     e->ai_canonname, uaddr, uport);
 293         freeaddrinfo(res);
 294         return sock;
 295     }
 296     freeaddrinfo(res);
 297     return -1;
 298 }
 299
 300 #ifndef _WIN32
 301
 302 int unix_listen(const char *str, char *ostr, int olen)
 303 {
 304     struct sockaddr_un un;
 305     char *path, *opts;
 306     int sock, fd, len;
 307
 308     sock = socket(PF_UNIX, SOCK_STREAM, 0);
 309     if (sock < 0) {
 310         perror("socket(unix)");
 311         return -1;
 312     }
 313
 314     opts = strchr(str, ',');
 315     if (opts) {
 316         len = opts - str;
 317         path = malloc(len+1);
 318         snprintf(path, len+1, "%.*s", len, str);
 319     } else
 320         path = strdup(str);
 321
 322     memset(&un, 0, sizeof(un));
 323     un.sun_family = AF_UNIX;
 324     if (path && strlen(path)) {
 325         snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
 326     } else {
 327         char *tmpdir = getenv("TMPDIR");
 328         snprintf(un.sun_path, sizeof(un.sun_path), "%s/qemu-socket-XXXXXX",
 329                  tmpdir ? tmpdir : "/tmp");
 330         /*
 331          * This dummy fd usage silences the mktemp() unsecure warning.
 332          * Using mkstemp() doesn't make things more secure here
 333          * though.  bind() complains about existing files, so we have
 334          * to unlink first and thus re-open the race window.  The
 335          * worst case possible is bind() failing, i.e. a DoS attack.
 336          */
 337         fd = mkstemp(un.sun_path); close(fd);
 338     }
 339     snprintf(ostr, olen, "%s%s", un.sun_path, opts ? opts : "");
 340
 341     unlink(un.sun_path);
 342     if (bind(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
 343         fprintf(stderr, "bind(unix:%s): %s\n", un.sun_path, strerror(errno));
 344         goto err;
 345     }
 346     if (listen(sock, 1) < 0) {
 347         fprintf(stderr, "listen(unix:%s): %s\n", un.sun_path, strerror(errno));
 348         goto err;
 349     }
 350
 351     if (sockets_debug)
 352         fprintf(stderr, "bind(unix:%s): OK\n", un.sun_path);
 353     free(path);
 354     return sock;
 355
 356 err:
 357     free(path);
 358     closesocket(sock);
 359     return -1;
 360 }
 361
 362 int unix_connect(const char *path)
 363 {
 364     struct sockaddr_un un;
 365     int sock;
 366
 367     sock = socket(PF_UNIX, SOCK_STREAM, 0);
 368     if (sock < 0) {
 369         perror("socket(unix)");
 370         return -1;
 371     }
 372
 373     memset(&un, 0, sizeof(un));
 374     un.sun_family = AF_UNIX;
 375     snprintf(un.sun_path, sizeof(un.sun_path), "%s", path);
 376     if (connect(sock, (struct sockaddr*) &un, sizeof(un)) < 0) {
 377         fprintf(stderr, "connect(unix:%s): %s\n", path, strerror(errno));
 378         return -1;
 379     }
 380
 381     if (sockets_debug)
 382         fprintf(stderr, "connect(unix:%s): OK\n", path);
 383     return sock;
 384 }
 385
 386 #else
 387
 388 int unix_listen(const char *path, char *ostr, int olen)
 389 {
 390     fprintf(stderr, "unix sockets are not available on windows\n");
 391     return -1;
 392 }
 393
 394 int unix_connect(const char *path)
 395 {
 396     fprintf(stderr, "unix sockets are not available on windows\n");
 397     return -1;
 398 }
 399
 400 #endif