curl/lib/connect.c

   1 /***************************************************************************
   2  *                                  _   _ ____  _
   3  *  Project                     ___| | | |  _ \| |
   4  *                             / __| | | | |_) | |
   5  *                            | (__| |_| |  _ <| |___
   6  *                             \___|\___/|_| \_\_____|
   7  *
   8  * Copyright (C) 1998 - 2008, Daniel Stenberg, <daniel@haxx.se>, et al.
   9  *
  10  * This software is licensed as described in the file COPYING, which
  11  * you should have received as part of this distribution. The terms
  12  * are also available at http://curl.haxx.se/docs/copyright.html.
  13  *
  14  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
  15  * copies of the Software, and permit persons to whom the Software is
  16  * furnished to do so, under the terms of the COPYING file.
  17  *
  18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  19  * KIND, either express or implied.
  20  *
  21  * $Id: connect.c,v 1.197 2008-08-26 21:28:57 danf Exp $
  22  ***************************************************************************/
  23
  24 #include "setup.h"
  25
  26 #ifndef WIN32
  27 /* headers for non-win32 */
  28 #ifdef HAVE_SYS_TIME_H
  29 #include <sys/time.h>
  30 #endif
  31 #ifdef HAVE_SYS_SOCKET_H
  32 #include <sys/socket.h>
  33 #endif
  34 #ifdef HAVE_NETINET_IN_H
  35 #include <netinet/in.h> /* <netinet/tcp.h> may need it */
  36 #endif
  37 #ifdef HAVE_SYS_UN_H
  38 #include <sys/un.h> /* for sockaddr_un */
  39 #endif
  40 #ifdef HAVE_NETINET_TCP_H
  41 #include <netinet/tcp.h> /* for TCP_NODELAY */
  42 #endif
  43 #ifdef HAVE_SYS_IOCTL_H
  44 #include <sys/ioctl.h>
  45 #endif
  46 #ifdef HAVE_UNISTD_H
  47 #include <unistd.h>
  48 #endif
  49 #ifdef HAVE_NETDB_H
  50 #include <netdb.h>
  51 #endif
  52 #ifdef HAVE_FCNTL_H
  53 #include <fcntl.h>
  54 #endif
  55 #ifdef HAVE_ARPA_INET_H
  56 #include <arpa/inet.h>
  57 #endif
  58 #ifdef HAVE_STDLIB_H
  59 #include <stdlib.h> /* required for free() prototype, without it, this crashes */
  60 #endif              /* on macos 68K */
  61
  62 #if (defined(HAVE_FIONBIO) && defined(NETWARE))
  63 #include <sys/filio.h>
  64 #endif
  65 #ifdef NETWARE
  66 #undef in_addr_t
  67 #define in_addr_t unsigned long
  68 #endif
  69 #ifdef VMS
  70 #include <in.h>
  71 #include <inet.h>
  72 #endif
  73
  74 #endif  /* !WIN32 */
  75
  76 #include <stdio.h>
  77 #include <errno.h>
  78 #include <string.h>
  79
  80 #define _MPRINTF_REPLACE /* use our functions only */
  81 #include <curl/mprintf.h>
  82
  83 #include "urldata.h"
  84 #include "sendf.h"
  85 #include "if2ip.h"
  86 #include "strerror.h"
  87 #include "connect.h"
  88 #include "memory.h"
  89 #include "select.h"
  90 #include "url.h" /* for Curl_safefree() */
  91 #include "multiif.h"
  92 #include "sockaddr.h" /* required for Curl_sockaddr_storage */
  93 #include "inet_ntop.h"
  94 #include "inet_pton.h"
  95 #include "sslgen.h" /* for Curl_ssl_check_cxn() */
  96
  97 /* The last #include file should be: */
  98 #include "memdebug.h"
  99
 100 #ifdef __SYMBIAN32__
 101 /* This isn't actually supported under Symbian OS */
 102 #undef SO_NOSIGPIPE
 103 #endif
 104
 105 static bool verifyconnect(curl_socket_t sockfd, int *error);
 106
 107 static curl_socket_t
 108 singleipconnect(struct connectdata *conn,
 109                 const Curl_addrinfo *ai, /* start connecting to this */
 110                 long timeout_ms,
 111                 bool *connected);
 112
 113 /*
 114  * Curl_timeleft() returns the amount of milliseconds left allowed for the
 115  * transfer/connection. If the value is negative, the timeout time has already
 116  * elapsed.
 117  *
 118  * If 'nowp' is non-NULL, it points to the current time.
 119  * 'duringconnect' is FALSE if not during a connect, as then of course the
 120  * connect timeout is not taken into account!
 121  */
 122 long Curl_timeleft(struct connectdata *conn,
 123                    struct timeval *nowp,
 124                    bool duringconnect)
 125 {
 126   struct SessionHandle *data = conn->data;
 127   int timeout_set = 0;
 128   long timeout_ms = duringconnect?DEFAULT_CONNECT_TIMEOUT:0;
 129   struct timeval now;
 130
 131   /* if a timeout is set, use the most restrictive one */
 132
 133   if(data->set.timeout > 0)
 134     timeout_set |= 1;
 135   if(duringconnect && (data->set.connecttimeout > 0))
 136     timeout_set |= 2;
 137
 138   switch (timeout_set) {
 139   case 1:
 140     timeout_ms = data->set.timeout;
 141     break;
 142   case 2:
 143     timeout_ms = data->set.connecttimeout;
 144     break;
 145   case 3:
 146     if(data->set.timeout < data->set.connecttimeout)
 147       timeout_ms = data->set.timeout;
 148     else
 149       timeout_ms = data->set.connecttimeout;
 150     break;
 151   default:
 152     /* use the default */
 153     if(!duringconnect)
 154       /* if we're not during connect, there's no default timeout so if we're
 155          at zero we better just return zero and not make it a negative number
 156          by the math below */
 157       return 0;
 158     break;
 159   }
 160
 161   if(!nowp) {
 162     now = Curl_tvnow();
 163     nowp = &now;
 164   }
 165
 166   /* substract elapsed time */
 167   timeout_ms -= Curl_tvdiff(*nowp, data->progress.t_startsingle);
 168
 169   return timeout_ms;
 170 }
 171
 172
 173 /*
 174  * Curl_nonblock() set the given socket to either blocking or non-blocking
 175  * mode based on the 'nonblock' boolean argument. This function is highly
 176  * portable.
 177  */
 178 int Curl_nonblock(curl_socket_t sockfd,    /* operate on this */
 179                   int nonblock   /* TRUE or FALSE */)
 180 {
 181 #undef SETBLOCK
 182 #define SETBLOCK 0
 183 #ifdef HAVE_O_NONBLOCK
 184   /* most recent unix versions */
 185   int flags;
 186
 187   flags = fcntl(sockfd, F_GETFL, 0);
 188   if(FALSE != nonblock)
 189     return fcntl(sockfd, F_SETFL, flags | O_NONBLOCK);
 190   else
 191     return fcntl(sockfd, F_SETFL, flags & (~O_NONBLOCK));
 192 #undef SETBLOCK
 193 #define SETBLOCK 1
 194 #endif
 195
 196 #if defined(HAVE_FIONBIO) && (SETBLOCK == 0)
 197   /* older unix versions */
 198   int flags;
 199
 200   flags = nonblock;
 201   return ioctl(sockfd, FIONBIO, &flags);
 202 #undef SETBLOCK
 203 #define SETBLOCK 2
 204 #endif
 205
 206 #if defined(HAVE_IOCTLSOCKET) && (SETBLOCK == 0)
 207   /* Windows? */
 208   unsigned long flags;
 209   flags = nonblock;
 210
 211   return ioctlsocket(sockfd, FIONBIO, &flags);
 212 #undef SETBLOCK
 213 #define SETBLOCK 3
 214 #endif
 215
 216 #if defined(HAVE_IOCTLSOCKET_CASE) && (SETBLOCK == 0)
 217   /* presumably for Amiga */
 218   return IoctlSocket(sockfd, FIONBIO, (long)nonblock);
 219 #undef SETBLOCK
 220 #define SETBLOCK 4
 221 #endif
 222
 223 #if defined(HAVE_SO_NONBLOCK) && (SETBLOCK == 0)
 224   /* BeOS */
 225   long b = nonblock ? 1 : 0;
 226   return setsockopt(sockfd, SOL_SOCKET, SO_NONBLOCK, &b, sizeof(b));
 227 #undef SETBLOCK
 228 #define SETBLOCK 5
 229 #endif
 230
 231 #ifdef HAVE_DISABLED_NONBLOCKING
 232   return 0; /* returns success */
 233 #undef SETBLOCK
 234 #define SETBLOCK 6
 235 #endif
 236
 237 #if(SETBLOCK == 0)
 238 #error "no non-blocking method was found/used/set"
 239 #endif
 240 }
 241
 242 /*
 243  * waitconnect() waits for a TCP connect on the given socket for the specified
 244  * number if milliseconds. It returns:
 245  * 0    fine connect
 246  * -1   select() error
 247  * 1    select() timeout
 248  * 2    select() returned with an error condition fd_set
 249  */
 250
 251 #define WAITCONN_CONNECTED     0
 252 #define WAITCONN_SELECT_ERROR -1
 253 #define WAITCONN_TIMEOUT       1
 254 #define WAITCONN_FDSET_ERROR   2
 255
 256 static
 257 int waitconnect(curl_socket_t sockfd, /* socket */
 258                 long timeout_msec)
 259 {
 260   int rc;
 261 #ifdef mpeix
 262   /* Call this function once now, and ignore the results. We do this to
 263      "clear" the error state on the socket so that we can later read it
 264      reliably. This is reported necessary on the MPE/iX operating system. */
 265   (void)verifyconnect(sockfd, NULL);
 266 #endif
 267
 268   /* now select() until we get connect or timeout */
 269   rc = Curl_socket_ready(CURL_SOCKET_BAD, sockfd, (int)timeout_msec);
 270   if(-1 == rc)
 271     /* error, no connect here, try next */
 272     return WAITCONN_SELECT_ERROR;
 273
 274   else if(0 == rc)
 275     /* timeout, no connect today */
 276     return WAITCONN_TIMEOUT;
 277
 278   if(rc & CURL_CSELECT_ERR)
 279     /* error condition caught */
 280     return WAITCONN_FDSET_ERROR;
 281
 282   /* we have a connect! */
 283   return WAITCONN_CONNECTED;
 284 }
 285
 286 static CURLcode bindlocal(struct connectdata *conn,
 287                           curl_socket_t sockfd)
 288 {
 289 #ifdef ENABLE_IPV6
 290   char ipv6_addr[16];
 291 #endif
 292   struct SessionHandle *data = conn->data;
 293   struct sockaddr_in me;
 294   struct sockaddr *sock = NULL;  /* bind to this address */
 295   socklen_t socksize; /* size of the data sock points to */
 296   unsigned short port = data->set.localport; /* use this port number, 0 for
 297                                                 "random" */
 298   /* how many port numbers to try to bind to, increasing one at a time */
 299   int portnum = data->set.localportrange;
 300   const char *dev = data->set.str[STRING_DEVICE];
 301
 302   /*************************************************************
 303    * Select device to bind socket to
 304    *************************************************************/
 305   if(dev && (strlen(dev)<255) ) {
 306     struct Curl_dns_entry *h=NULL;
 307     char myhost[256] = "";
 308     in_addr_t in;
 309     int rc;
 310     bool was_iface = FALSE;
 311     int in6 = -1;
 312
 313     /* First check if the given name is an IP address */
 314     in=inet_addr((char *) dev);
 315
 316     if((in == CURL_INADDR_NONE) &&
 317        Curl_if2ip(dev, myhost, sizeof(myhost))) {
 318       /*
 319        * We now have the numerical IPv4-style x.y.z.w in the 'myhost' buffer
 320        */
 321       rc = Curl_resolv(conn, myhost, 0, &h);
 322       if(rc == CURLRESOLV_PENDING)
 323         (void)Curl_wait_for_resolv(conn, &h);
 324
 325       if(h) {
 326         was_iface = TRUE;
 327         Curl_resolv_unlock(data, h);
 328       }
 329     }
 330
 331     if(!was_iface) {
 332       /*
 333        * This was not an interface, resolve the name as a host name
 334        * or IP number
 335        */
 336       rc = Curl_resolv(conn, dev, 0, &h);
 337       if(rc == CURLRESOLV_PENDING)
 338         (void)Curl_wait_for_resolv(conn, &h);
 339
 340       if(h) {
 341         if(in == CURL_INADDR_NONE)
 342           /* convert the resolved address, sizeof myhost >= INET_ADDRSTRLEN */
 343           Curl_printable_address(h->addr, myhost, sizeof myhost);
 344         else
 345           /* we know data->set.device is shorter than the myhost array */
 346           strcpy(myhost, dev);
 347         Curl_resolv_unlock(data, h);
 348       }
 349     }
 350
 351     if(! *myhost) {
 352       /* need to fix this
 353          h=Curl_gethost(data,
 354          getmyhost(*myhost,sizeof(myhost)),
 355          hostent_buf,
 356          sizeof(hostent_buf));
 357       */
 358       failf(data, "Couldn't bind to '%s'", dev);
 359       return CURLE_INTERFACE_FAILED;
 360     }
 361
 362     infof(data, "Bind local address to %s\n", myhost);
 363
 364 #ifdef SO_BINDTODEVICE
 365     /* I am not sure any other OSs than Linux that provide this feature, and
 366      * at the least I cannot test. --Ben
 367      *
 368      * This feature allows one to tightly bind the local socket to a
 369      * particular interface.  This will force even requests to other local
 370      * interfaces to go out the external interface.
 371      *
 372      */
 373     if(was_iface) {
 374       /* Only bind to the interface when specified as interface, not just as a
 375        * hostname or ip address.
 376        */
 377       if(setsockopt(sockfd, SOL_SOCKET, SO_BINDTODEVICE,
 378                      dev, strlen(dev)+1) != 0) {
 379         /* printf("Failed to BINDTODEVICE, socket: %d  device: %s error: %s\n",
 380            sockfd, dev, Curl_strerror(SOCKERRNO)); */
 381         infof(data, "SO_BINDTODEVICE %s failed\n", dev);
 382         /* This is typically "errno 1, error: Operation not permitted" if
 383            you're not running as root or another suitable privileged user */
 384       }
 385     }
 386 #endif
 387
 388     in=inet_addr(myhost);
 389
 390 #ifdef ENABLE_IPV6
 391     in6 = Curl_inet_pton (AF_INET6, myhost, (void *)&ipv6_addr);
 392 #endif
 393     if(CURL_INADDR_NONE == in && -1 == in6) {
 394       failf(data,"couldn't find my own IP address (%s)", myhost);
 395       return CURLE_INTERFACE_FAILED;
 396     } /* end of inet_addr */
 397
 398     if( h ) {
 399       Curl_addrinfo *addr = h->addr;
 400       sock = addr->ai_addr;
 401       socksize = addr->ai_addrlen;
 402     }
 403     else
 404       return CURLE_INTERFACE_FAILED;
 405
 406   }
 407   else if(port) {
 408     /* if a local port number is requested but no local IP, extract the
 409        address from the socket */
 410     memset(&me, 0, sizeof(struct sockaddr));
 411     me.sin_family = AF_INET;
 412     me.sin_addr.s_addr = INADDR_ANY;
 413
 414     sock = (struct sockaddr *)&me;
 415     socksize = sizeof(struct sockaddr);
 416
 417   }
 418   else
 419     /* no local kind of binding was requested */
 420     return CURLE_OK;
 421
 422   do {
 423
 424     /* Set port number to bind to, 0 makes the system pick one */
 425     if(sock->sa_family == AF_INET)
 426       ((struct sockaddr_in *)sock)->sin_port = htons(port);
 427 #ifdef ENABLE_IPV6
 428     else
 429       ((struct sockaddr_in6 *)sock)->sin6_port = htons(port);
 430 #endif
 431
 432     if( bind(sockfd, sock, socksize) >= 0) {
 433       /* we succeeded to bind */
 434       struct Curl_sockaddr_storage add;
 435       socklen_t size;
 436
 437       size = sizeof(add);
 438       if(getsockname(sockfd, (struct sockaddr *) &add, &size) < 0) {
 439         failf(data, "getsockname() failed");
 440         return CURLE_INTERFACE_FAILED;
 441       }
 442       /* We re-use/clobber the port variable here below */
 443       if(((struct sockaddr *)&add)->sa_family == AF_INET)
 444         port = ntohs(((struct sockaddr_in *)&add)->sin_port);
 445 #ifdef ENABLE_IPV6
 446       else
 447         port = ntohs(((struct sockaddr_in6 *)&add)->sin6_port);
 448 #endif
 449       infof(data, "Local port: %d\n", port);
 450       conn->bits.bound = TRUE;
 451       return CURLE_OK;
 452     }
 453     if(--portnum > 0) {
 454       infof(data, "Bind to local port %d failed, trying next\n", port);
 455       port++; /* try next port */
 456     }
 457     else
 458       break;
 459   } while(1);
 460
 461   data->state.os_errno = SOCKERRNO;
 462   failf(data, "bind failure: %s",
 463         Curl_strerror(conn, data->state.os_errno));
 464   return CURLE_INTERFACE_FAILED;
 465
 466 }
 467
 468 /*
 469  * verifyconnect() returns TRUE if the connect really has happened.
 470  */
 471 static bool verifyconnect(curl_socket_t sockfd, int *error)
 472 {
 473   bool rc = TRUE;
 474 #ifdef SO_ERROR
 475   int err = 0;
 476   socklen_t errSize = sizeof(err);
 477
 478 #ifdef WIN32
 479   /*
 480    * In October 2003 we effectively nullified this function on Windows due to
 481    * problems with it using all CPU in multi-threaded cases.
 482    *
 483    * In May 2004, we bring it back to offer more info back on connect failures.
 484    * Gisle Vanem could reproduce the former problems with this function, but
 485    * could avoid them by adding this SleepEx() call below:
 486    *
 487    *    "I don't have Rational Quantify, but the hint from his post was
 488    *    ntdll::NtRemoveIoCompletion(). So I'd assume the SleepEx (or maybe
 489    *    just Sleep(0) would be enough?) would release whatever
 490    *    mutex/critical-section the ntdll call is waiting on.
 491    *
 492    *    Someone got to verify this on Win-NT 4.0, 2000."
 493    */
 494
 495 #ifdef _WIN32_WCE
 496   Sleep(0);
 497 #else
 498   SleepEx(0, FALSE);
 499 #endif
 500
 501 #endif
 502
 503   if(0 != getsockopt(sockfd, SOL_SOCKET, SO_ERROR, (void *)&err, &errSize))
 504     err = SOCKERRNO;
 505 #ifdef _WIN32_WCE
 506   /* Old WinCE versions don't support SO_ERROR */
 507   if(WSAENOPROTOOPT == err) {
 508     SET_SOCKERRNO(0);
 509     err = 0;
 510   }
 511 #endif
 512 #ifdef __minix
 513   /* Minix 3.1.x doesn't support getsockopt on UDP sockets */
 514   if(EBADIOCTL == err) {
 515     SET_SOCKERRNO(0);
 516     err = 0;
 517   }
 518 #endif
 519   if((0 == err) || (EISCONN == err))
 520     /* we are connected, awesome! */
 521     rc = TRUE;
 522   else
 523     /* This wasn't a successful connect */
 524     rc = FALSE;
 525   if(error)
 526     *error = err;
 527 #else
 528   (void)sockfd;
 529   if(error)
 530     *error = SOCKERRNO;
 531 #endif
 532   return rc;
 533 }
 534
 535 CURLcode Curl_store_ip_addr(struct connectdata *conn)
 536 {
 537   char addrbuf[256];
 538   Curl_printable_address(conn->ip_addr, addrbuf, sizeof(addrbuf));
 539
 540   /* save the string */
 541   Curl_safefree(conn->ip_addr_str);
 542   conn->ip_addr_str = strdup(addrbuf);
 543   if(!conn->ip_addr_str)
 544     return CURLE_OUT_OF_MEMORY; /* FAIL */
 545
 546 #ifdef PF_INET6
 547   if(conn->ip_addr->ai_family == PF_INET6)
 548     conn->bits.ipv6 = TRUE;
 549 #endif
 550
 551   return CURLE_OK;
 552 }
 553
 554 /* Used within the multi interface. Try next IP address, return TRUE if no
 555    more address exists or error */
 556 static bool trynextip(struct connectdata *conn,
 557                       int sockindex,
 558                       bool *connected)
 559 {
 560   curl_socket_t sockfd;
 561   Curl_addrinfo *ai;
 562
 563   /* first close the failed socket */
 564   sclose(conn->sock[sockindex]);
 565   conn->sock[sockindex] = CURL_SOCKET_BAD;
 566   *connected = FALSE;
 567
 568   if(sockindex != FIRSTSOCKET)
 569     return TRUE; /* no next */
 570
 571   /* try the next address */
 572   ai = conn->ip_addr->ai_next;
 573
 574   while(ai) {
 575     sockfd = singleipconnect(conn, ai, 0L, connected);
 576     if(sockfd != CURL_SOCKET_BAD) {
 577       /* store the new socket descriptor */
 578       conn->sock[sockindex] = sockfd;
 579       conn->ip_addr = ai;
 580
 581       return Curl_store_ip_addr(conn) != CURLE_OK;
 582     }
 583     ai = ai->ai_next;
 584   }
 585   return TRUE;
 586 }
 587
 588 /*
 589  * Curl_is_connected() is used from the multi interface to check if the
 590  * firstsocket has connected.
 591  */
 592
 593 CURLcode Curl_is_connected(struct connectdata *conn,
 594                            int sockindex,
 595                            bool *connected)
 596 {
 597   int rc;
 598   struct SessionHandle *data = conn->data;
 599   CURLcode code = CURLE_OK;
 600   curl_socket_t sockfd = conn->sock[sockindex];
 601   long allow = DEFAULT_CONNECT_TIMEOUT;
 602
 603   DEBUGASSERT(sockindex >= FIRSTSOCKET && sockindex <= SECONDARYSOCKET);
 604
 605   *connected = FALSE; /* a very negative world view is best */
 606
 607   if(conn->bits.tcpconnect) {
 608     /* we are connected already! */
 609     long allow_total = 0;
 610
 611     /* subtract the most strict timeout of the ones */
 612     if(data->set.timeout)
 613       allow_total = data->set.timeout;
 614
 615     Curl_expire(data, allow_total);
 616     *connected = TRUE;
 617     return CURLE_OK;
 618   }
 619
 620   /* figure out how long time we have left to connect */
 621   allow = Curl_timeleft(conn, NULL, TRUE);
 622
 623   if(allow < 0) {
 624     /* time-out, bail out, go home */
 625     failf(data, "Connection time-out");
 626     return CURLE_OPERATION_TIMEDOUT;
 627   }
 628
 629   Curl_expire(data, allow);
 630
 631   /* check for connect without timeout as we want to return immediately */
 632   rc = waitconnect(sockfd, 0);
 633
 634   if(WAITCONN_CONNECTED == rc) {
 635     int error;
 636     if(verifyconnect(sockfd, &error)) {
 637       /* we are connected, awesome! */
 638       *connected = TRUE;
 639       return CURLE_OK;
 640     }
 641     /* nope, not connected for real */
 642     data->state.os_errno = error;
 643     infof(data, "Connection failed\n");
 644     if(trynextip(conn, sockindex, connected)) {
 645       failf(data, "Failed connect to %s:%d; %s",
 646             conn->host.name, conn->port, Curl_strerror(conn, error));
 647       code = CURLE_COULDNT_CONNECT;
 648     }
 649   }
 650   else if(WAITCONN_TIMEOUT != rc) {
 651     int error = 0;
 652
 653     /* nope, not connected  */
 654     if(WAITCONN_FDSET_ERROR == rc) {
 655       (void)verifyconnect(sockfd, &error);
 656       data->state.os_errno = error;
 657       infof(data, "%s\n",Curl_strerror(conn,error));
 658     }
 659     else
 660       infof(data, "Connection failed\n");
 661
 662     if(trynextip(conn, sockindex, connected)) {
 663       error = SOCKERRNO;
 664       data->state.os_errno = error;
 665       failf(data, "Failed connect to %s:%d; %s",
 666             conn->host.name, conn->port, Curl_strerror(conn, error));
 667       code = CURLE_COULDNT_CONNECT;
 668     }
 669   }
 670   /*
 671    * If the connection failed here, we should attempt to connect to the "next
 672    * address" for the given host.
 673    */
 674
 675   return code;
 676 }
 677
 678 static void tcpnodelay(struct connectdata *conn,
 679                        curl_socket_t sockfd)
 680 {
 681 #ifdef TCP_NODELAY
 682   struct SessionHandle *data= conn->data;
 683   socklen_t onoff = (socklen_t) data->set.tcp_nodelay;
 684   int proto = IPPROTO_TCP;
 685
 686 #if 0
 687   /* The use of getprotobyname() is disabled since it isn't thread-safe on
 688      numerous systems. On these getprotobyname_r() should be used instead, but
 689      that exists in at least one 4 arg version and one 5 arg version, and
 690      since the proto number rarely changes anyway we now just use the hard
 691      coded number. The "proper" fix would need a configure check for the
 692      correct function much in the same style the gethostbyname_r versions are
 693      detected. */
 694   struct protoent *pe = getprotobyname("tcp");
 695   if(pe)
 696     proto = pe->p_proto;
 697 #endif
 698
 699   if(setsockopt(sockfd, proto, TCP_NODELAY, (void *)&onoff,
 700                 sizeof(onoff)) < 0)
 701     infof(data, "Could not set TCP_NODELAY: %s\n",
 702           Curl_strerror(conn, SOCKERRNO));
 703   else
 704     infof(data,"TCP_NODELAY set\n");
 705 #else
 706   (void)conn;
 707   (void)sockfd;
 708 #endif
 709 }
 710
 711 #ifdef SO_NOSIGPIPE
 712 /* The preferred method on Mac OS X (10.2 and later) to prevent SIGPIPEs when
 713    sending data to a dead peer (instead of relying on the 4th argument to send
 714    being MSG_NOSIGNAL). Possibly also existing and in use on other BSD
 715    systems? */
 716 static void nosigpipe(struct connectdata *conn,
 717                       curl_socket_t sockfd)
 718 {
 719   struct SessionHandle *data= conn->data;
 720   int onoff = 1;
 721   if(setsockopt(sockfd, SOL_SOCKET, SO_NOSIGPIPE, (void *)&onoff,
 722                 sizeof(onoff)) < 0)
 723     infof(data, "Could not set SO_NOSIGPIPE: %s\n",
 724           Curl_strerror(conn, SOCKERRNO));
 725 }
 726 #else
 727 #define nosigpipe(x,y)
 728 #endif
 729
 730 /* singleipconnect() connects to the given IP only, and it may return without
 731    having connected if used from the multi interface. */
 732 static curl_socket_t
 733 singleipconnect(struct connectdata *conn,
 734                 const Curl_addrinfo *ai,
 735                 long timeout_ms,
 736                 bool *connected)
 737 {
 738   char addr_buf[128];
 739   int rc;
 740   int error;
 741   bool isconnected;
 742   struct SessionHandle *data = conn->data;
 743   curl_socket_t sockfd;
 744   CURLcode res;
 745   /*
 746    * Curl_sockaddr_storage, which is basically sockaddr_storage has a space
 747    * for a largest possible struct sockaddr only. We should add some space for
 748    * the other fields we are using. Hence the addr_storage size math.
 749    */
 750   char addr_storage[sizeof(struct curl_sockaddr)-
 751                     sizeof(struct sockaddr)+
 752                     sizeof(struct Curl_sockaddr_storage)];
 753   struct curl_sockaddr *addr=(struct curl_sockaddr*)&addr_storage;
 754   const void *iptoprint;
 755
 756   addr->family=ai->ai_family;
 757   addr->socktype=conn->socktype;
 758   addr->protocol=ai->ai_protocol;
 759   addr->addrlen =
 760     (ai->ai_addrlen < (socklen_t)sizeof(struct Curl_sockaddr_storage)) ?
 761      (unsigned int)ai->ai_addrlen : sizeof(struct Curl_sockaddr_storage);
 762   memcpy(&addr->addr, ai->ai_addr, addr->addrlen);
 763
 764   /* If set, use opensocket callback to get the socket */
 765   if(data->set.fopensocket)
 766     sockfd = data->set.fopensocket(data->set.opensocket_client,
 767                                    CURLSOCKTYPE_IPCXN, addr);
 768   else
 769     sockfd = socket(addr->family, addr->socktype, addr->protocol);
 770   if(sockfd == CURL_SOCKET_BAD)
 771     return CURL_SOCKET_BAD;
 772
 773   *connected = FALSE; /* default is not connected */
 774
 775 #ifdef CURLRES_IPV6
 776   if (conn->scope && (addr->family == AF_INET6)) {
 777     struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)&addr->addr;
 778     in6->sin6_scope_id = conn->scope;
 779   }
 780 #endif
 781
 782   /* FIXME: do we have Curl_printable_address-like with struct sockaddr* as
 783      argument? */
 784 #if defined(HAVE_SYS_UN_H) && defined(AF_UNIX)
 785   if(addr->family==AF_UNIX) {
 786     infof(data, "  Trying %s... ",
 787           ((const struct sockaddr_un*)(&addr->addr))->sun_path);
 788     snprintf(data->info.ip, MAX_IPADR_LEN, "%s",
 789              ((const struct sockaddr_un*)(&addr->addr))->sun_path);
 790   }
 791   else
 792 #endif
 793   {
 794 #ifdef ENABLE_IPV6
 795     if(addr->family==AF_INET6)
 796       iptoprint= &((const struct sockaddr_in6*)(&addr->addr))->sin6_addr;
 797     else
 798 #endif
 799       iptoprint = &((const struct sockaddr_in*)(&addr->addr))->sin_addr;
 800
 801     if(Curl_inet_ntop(addr->family, iptoprint, addr_buf,
 802                       sizeof(addr_buf)) != NULL) {
 803       infof(data, "  Trying %s... ", addr_buf);
 804       snprintf(data->info.ip, MAX_IPADR_LEN, "%s", addr_buf);
 805     }
 806   }
 807
 808   if(data->set.tcp_nodelay)
 809     tcpnodelay(conn, sockfd);
 810
 811   nosigpipe(conn, sockfd);
 812
 813   if(data->set.fsockopt) {
 814     /* activate callback for setting socket options */
 815     error = data->set.fsockopt(data->set.sockopt_client,
 816                                sockfd,
 817                                CURLSOCKTYPE_IPCXN);
 818     if(error) {
 819       sclose(sockfd); /* close the socket and bail out */
 820       return CURL_SOCKET_BAD;
 821     }
 822   }
 823
 824   /* possibly bind the local end to an IP, interface or port */
 825   res = bindlocal(conn, sockfd);
 826   if(res) {
 827     sclose(sockfd); /* close socket and bail out */
 828     return CURL_SOCKET_BAD;
 829   }
 830
 831   /* set socket non-blocking */
 832   Curl_nonblock(sockfd, TRUE);
 833
 834   /* Connect TCP sockets, bind UDP */
 835   if(conn->socktype == SOCK_STREAM)
 836     rc = connect(sockfd, &addr->addr, addr->addrlen);
 837   else
 838     rc = 0;
 839
 840   if(-1 == rc) {
 841     error = SOCKERRNO;
 842
 843     switch (error) {
 844     case EINPROGRESS:
 845     case EWOULDBLOCK:
 846 #if defined(EAGAIN) && EAGAIN != EWOULDBLOCK
 847       /* On some platforms EAGAIN and EWOULDBLOCK are the
 848        * same value, and on others they are different, hence
 849        * the odd #if
 850        */
 851     case EAGAIN:
 852 #endif
 853       rc = waitconnect(sockfd, timeout_ms);
 854       break;
 855     default:
 856       /* unknown error, fallthrough and try another address! */
 857       failf(data, "Failed to connect to %s: %s",
 858             addr_buf, Curl_strerror(conn,error));
 859       data->state.os_errno = error;
 860       break;
 861     }
 862   }
 863
 864   /* The 'WAITCONN_TIMEOUT == rc' comes from the waitconnect(), and not from
 865      connect(). We can be sure of this since connect() cannot return 1. */
 866   if((WAITCONN_TIMEOUT == rc) &&
 867      (data->state.used_interface == Curl_if_multi)) {
 868     /* Timeout when running the multi interface */
 869     return sockfd;
 870   }
 871
 872   isconnected = verifyconnect(sockfd, &error);
 873
 874   if(!rc && isconnected) {
 875     /* we are connected, awesome! */
 876     *connected = TRUE; /* this is a true connect */
 877     infof(data, "connected\n");
 878     return sockfd;
 879   }
 880   else if(WAITCONN_TIMEOUT == rc)
 881     infof(data, "Timeout\n");
 882   else {
 883     data->state.os_errno = error;
 884     infof(data, "%s\n", Curl_strerror(conn, error));
 885   }
 886
 887   /* connect failed or timed out */
 888   sclose(sockfd);
 889
 890   return CURL_SOCKET_BAD;
 891 }
 892
 893 /*
 894  * TCP connect to the given host with timeout, proxy or remote doesn't matter.
 895  * There might be more than one IP address to try out. Fill in the passed
 896  * pointer with the connected socket.
 897  */
 898
 899 CURLcode Curl_connecthost(struct connectdata *conn,  /* context */
 900                           const struct Curl_dns_entry *remotehost,
 901                           curl_socket_t *sockconn,   /* the connected socket */
 902                           Curl_addrinfo **addr,      /* the one we used */
 903                           bool *connected)           /* really connected? */
 904 {
 905   struct SessionHandle *data = conn->data;
 906   curl_socket_t sockfd = CURL_SOCKET_BAD;
 907   int aliasindex;
 908   int num_addr;
 909   Curl_addrinfo *ai;
 910   Curl_addrinfo *curr_addr;
 911
 912   struct timeval after;
 913   struct timeval before = Curl_tvnow();
 914
 915   /*************************************************************
 916    * Figure out what maximum time we have left
 917    *************************************************************/
 918   long timeout_ms;
 919   long timeout_per_addr;
 920
 921   DEBUGASSERT(sockconn);
 922   *connected = FALSE; /* default to not connected */
 923
 924   /* get the timeout left */
 925   timeout_ms = Curl_timeleft(conn, &before, TRUE);
 926
 927   if(timeout_ms < 0) {
 928     /* a precaution, no need to continue if time already is up */
 929     failf(data, "Connection time-out");
 930     return CURLE_OPERATION_TIMEDOUT;
 931   }
 932   Curl_expire(data, timeout_ms);
 933
 934   /* Max time for each address */
 935   num_addr = Curl_num_addresses(remotehost->addr);
 936   timeout_per_addr = timeout_ms / num_addr;
 937
 938   ai = remotehost->addr;
 939
 940   /* Below is the loop that attempts to connect to all IP-addresses we
 941    * know for the given host. One by one until one IP succeeds.
 942    */
 943
 944   if(data->state.used_interface == Curl_if_multi)
 945     /* don't hang when doing multi */
 946     timeout_per_addr = 0;
 947
 948   /*
 949    * Connecting with a Curl_addrinfo chain
 950    */
 951   for (curr_addr = ai, aliasindex=0; curr_addr;
 952        curr_addr = curr_addr->ai_next, aliasindex++) {
 953
 954     /* start connecting to the IP curr_addr points to */
 955     sockfd = singleipconnect(conn, curr_addr, timeout_per_addr, connected);
 956
 957     if(sockfd != CURL_SOCKET_BAD)
 958       break;
 959
 960     /* get a new timeout for next attempt */
 961     after = Curl_tvnow();
 962     timeout_ms -= Curl_tvdiff(after, before);
 963     if(timeout_ms < 0) {
 964       failf(data, "connect() timed out!");
 965       return CURLE_OPERATION_TIMEDOUT;
 966     }
 967     before = after;
 968   }  /* end of connect-to-each-address loop */
 969
 970   *sockconn = sockfd;    /* the socket descriptor we've connected */
 971
 972   if(sockfd == CURL_SOCKET_BAD) {
 973     /* no good connect was made */
 974     failf(data, "couldn't connect to host");
 975     return CURLE_COULDNT_CONNECT;
 976   }
 977
 978   /* leave the socket in non-blocking mode */
 979
 980   /* store the address we use */
 981   if(addr)
 982     *addr = curr_addr;
 983
 984   data->info.numconnects++; /* to track the number of connections made */
 985
 986   return CURLE_OK;
 987 }
 988
 989 /*
 990  * Used to extract socket and connectdata struct for the most recent
 991  * transfer on the given SessionHandle.
 992  *
 993  * The socket 'long' will be -1 in case of failure!
 994  */
 995 CURLcode Curl_getconnectinfo(struct SessionHandle *data,
 996                              long *param_longp,
 997                              struct connectdata **connp)
 998 {
 999   if((data->state.lastconnect != -1) &&
1000      (data->state.connc->connects[data->state.lastconnect] != NULL)) {
1001     struct connectdata *c =
1002       data->state.connc->connects[data->state.lastconnect];
1003     if(connp)
1004       /* only store this if the caller cares for it */
1005       *connp = c;
1006     *param_longp = c->sock[FIRSTSOCKET];
1007     /* we have a socket connected, let's determine if the server shut down */
1008     /* determine if ssl */
1009     if(c->ssl[FIRSTSOCKET].use) {
1010       /* use the SSL context */
1011       if(!Curl_ssl_check_cxn(c))
1012         *param_longp = -1;   /* FIN received */
1013     }
1014 /* Minix 3.1 doesn't support any flags on recv; just assume socket is OK */
1015 #ifdef MSG_PEEK
1016     else {
1017       /* use the socket */
1018       char buf;
1019       if(recv((RECV_TYPE_ARG1)c->sock[FIRSTSOCKET], (RECV_TYPE_ARG2)&buf,
1020               (RECV_TYPE_ARG3)1, (RECV_TYPE_ARG4)MSG_PEEK) == 0) {
1021         *param_longp = -1;   /* FIN received */
1022       }
1023     }
1024 #endif
1025   }
1026   else
1027     *param_longp = -1;
1028
1029   return CURLE_OK;
1030 }