libcurl extracted to the separate lib

git-svn-id: http://svn.miranda-ng.org/main/trunk@14683 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c

1 files changed, 1331 insertions, 0 deletions

diff --git a/libs/libcurl/src/connect.c b/libs/libcurl/src/connect.c
new file mode 100644
index 0000000000..2b5719d123
--- /dev/null
+++ b/libs/libcurl/src/connect.c
@@ -0,0 +1,1331 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+
+#ifdef HAVE_NETINET_IN_H
+#include <netinet/in.h> /* <netinet/tcp.h> may need it */
+#endif
+#ifdef HAVE_SYS_UN_H
+#include <sys/un.h> /* for sockaddr_un */
+#endif
+#ifdef HAVE_NETINET_TCP_H
+#include <netinet/tcp.h> /* for TCP_NODELAY */
+#endif
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+#ifdef HAVE_NETDB_H
+#include <netdb.h>
+#endif
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#ifdef HAVE_ARPA_INET_H
+#include <arpa/inet.h>
+#endif
+
+#if (defined(HAVE_IOCTL_FIONBIO) && defined(NETWARE))
+#include <sys/filio.h>
+#endif
+#ifdef NETWARE
+#undef in_addr_t
+#define in_addr_t unsigned long
+#endif
+#ifdef __VMS
+#include <in.h>
+#include <inet.h>
+#endif
+
+#define _MPRINTF_REPLACE /* use our functions only */
+#include <curl/mprintf.h>
+
+#include "urldata.h"
+#include "sendf.h"
+#include "if2ip.h"
+#include "strerror.h"
+#include "connect.h"
+#include "curl_memory.h"
+#include "select.h"
+#include "url.h" /* for Curl_safefree() */
+#include "multiif.h"
+#include "sockaddr.h" /* required for Curl_sockaddr_storage */
+#include "inet_ntop.h"
+#include "inet_pton.h"
+#include "sslgen.h" /* for Curl_ssl_check_cxn() */
+#include "progress.h"
+#include "warnless.h"
+#include "conncache.h"
+#include "multihandle.h"
+
+/* The last #include file should be: */
+#include "memdebug.h"
+
+#ifdef __SYMBIAN32__
+/* This isn't actually supported under Symbian OS */
+#undef SO_NOSIGPIPE
+#endif
+
+static bool verifyconnect(curl_socket_t sockfd, int *error);
+
+#if defined(__DragonFly__) || defined(HAVE_WINSOCK_H)
+/* DragonFlyBSD and Windows use millisecond units */
+#define KEEPALIVE_FACTOR(x) (x *= 1000)
+#else
+#define KEEPALIVE_FACTOR(x)
+#endif
+
+#if defined(HAVE_WINSOCK_H) && !defined(SIO_KEEPALIVE_VALS)
+#define SIO_KEEPALIVE_VALS    _WSAIOW(IOC_VENDOR,4)
+
+struct tcp_keepalive {
+  u_long onoff;
+  u_long keepalivetime;
+  u_long keepaliveinterval;
+};
+#endif
+
+static void
+tcpkeepalive(struct SessionHandle *data,
+             curl_socket_t sockfd)
+{
+  int optval = data->set.tcp_keepalive?1:0;
+
+  /* only set IDLE and INTVL if setting KEEPALIVE is successful */
+  if(setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE,
+        (void *)&optval, sizeof(optval)) < 0) {
+    infof(data, "Failed to set SO_KEEPALIVE on fd %d\n", sockfd);
+  }
+  else {
+#if defined(SIO_KEEPALIVE_VALS)
+    struct tcp_keepalive vals;
+    DWORD dummy;
+    vals.onoff = 1;
+    optval = curlx_sltosi(data->set.tcp_keepidle);
+    KEEPALIVE_FACTOR(optval);
+    vals.keepalivetime = optval;
+    optval = curlx_sltosi(data->set.tcp_keepintvl);
+    KEEPALIVE_FACTOR(optval);
+    vals.keepaliveinterval = optval;
+    if(WSAIoctl(sockfd, SIO_KEEPALIVE_VALS, (LPVOID) &vals, sizeof(vals),
+                NULL, 0, &dummy, NULL, NULL) != 0) {
+      infof(data, "Failed to set SIO_KEEPALIVE_VALS on fd %d: %d\n",
+            (int)sockfd, WSAGetLastError());
+    }
+#else
+#ifdef TCP_KEEPIDLE
+    optval = curlx_sltosi(data->set.tcp_keepidle);
+    KEEPALIVE_FACTOR(optval);
+    if(setsockopt(sockfd, IPPROTO_TCP, TCP_KEEPIDLE,
+          (void *)&optval, sizeof(optval)) < 0) {
+      infof(data, "Failed to set TCP_KEEPIDLE on fd %d\n", sockfd);
+    }
+#endif
+#ifdef TCP_KEEPINTVL
+    optval = curlx_sltosi(data->set.tcp_keepintvl);
+    KEEPALIVE_FACTOR(optval);
+    if(setsockopt(sockfd, IPPROTO_TCP, TCP_KEEPINTVL,
+          (void *)&optval, sizeof(optval)) < 0) {
+      infof(data, "Failed to set TCP_KEEPINTVL on fd %d\n", sockfd);
+    }
+#endif
+#ifdef TCP_KEEPALIVE
+    /* Mac OS X style */
+    optval = curlx_sltosi(data->set.tcp_keepidle);
+    KEEPALIVE_FACTOR(optval);
+    if(setsockopt(sockfd, IPPROTO_TCP, TCP_KEEPALIVE,
+          (void *)&optval, sizeof(optval)) < 0) {
+      infof(data, "Failed to set TCP_KEEPALIVE on fd %d\n", sockfd);
+    }
+#endif
+#endif
+  }
+}
+
+static CURLcode
+singleipconnect(struct connectdata *conn,
+                const Curl_addrinfo *ai, /* start connecting to this */
+                curl_socket_t *sock,
+                bool *connected);
+
+/*
+ * Curl_timeleft() returns the amount of milliseconds left allowed for the
+ * transfer/connection. If the value is negative, the timeout time has already
+ * elapsed.
+ *
+ * The start time is stored in progress.t_startsingle - as set with
+ * Curl_pgrsTime(..., TIMER_STARTSINGLE);
+ *
+ * If 'nowp' is non-NULL, it points to the current time.
+ * 'duringconnect' is FALSE if not during a connect, as then of course the
+ * connect timeout is not taken into account!
+ *
+ * @unittest: 1303
+ */
+long Curl_timeleft(struct SessionHandle *data,
+                   struct timeval *nowp,
+                   bool duringconnect)
+{
+  int timeout_set = 0;
+  long timeout_ms = duringconnect?DEFAULT_CONNECT_TIMEOUT:0;
+  struct timeval now;
+
+  /* if a timeout is set, use the most restrictive one */
+
+  if(data->set.timeout > 0)
+    timeout_set |= 1;
+  if(duringconnect && (data->set.connecttimeout > 0))
+    timeout_set |= 2;
+
+  switch (timeout_set) {
+  case 1:
+    timeout_ms = data->set.timeout;
+    break;
+  case 2:
+    timeout_ms = data->set.connecttimeout;
+    break;
+  case 3:
+    if(data->set.timeout < data->set.connecttimeout)
+      timeout_ms = data->set.timeout;
+    else
+      timeout_ms = data->set.connecttimeout;
+    break;
+  default:
+    /* use the default */
+    if(!duringconnect)
+      /* if we're not during connect, there's no default timeout so if we're
+         at zero we better just return zero and not make it a negative number
+         by the math below */
+      return 0;
+    break;
+  }
+
+  if(!nowp) {
+    now = Curl_tvnow();
+    nowp = &now;
+  }
+
+  /* subtract elapsed time */
+  timeout_ms -= Curl_tvdiff(*nowp, data->progress.t_startsingle);
+  if(!timeout_ms)
+    /* avoid returning 0 as that means no timeout! */
+    return -1;
+
+  return timeout_ms;
+}
+
+/*
+ * checkconnect() checks for a TCP connect on the given socket.
+ * It returns:
+ */
+
+enum chkconn_t {
+  CHKCONN_SELECT_ERROR = -1,
+  CHKCONN_CONNECTED    = 0,
+  CHKCONN_IDLE         = 1,
+  CHKCONN_FDSET_ERROR  = 2
+};
+
+static enum chkconn_t
+checkconnect(curl_socket_t sockfd)
+{
+  int rc;
+#ifdef mpeix
+  /* Call this function once now, and ignore the results. We do this to
+     "clear" the error state on the socket so that we can later read it
+     reliably. This is reported necessary on the MPE/iX operating system. */
+  (void)verifyconnect(sockfd, NULL);
+#endif
+
+  rc = Curl_socket_ready(CURL_SOCKET_BAD, sockfd, 0);
+
+  if(-1 == rc)
+    /* error, no connect here, try next */
+    return CHKCONN_SELECT_ERROR;
+
+  else if(rc & CURL_CSELECT_ERR)
+    /* error condition caught */
+    return CHKCONN_FDSET_ERROR;
+
+  else if(rc)
+    return CHKCONN_CONNECTED;
+
+  return CHKCONN_IDLE;
+}
+
+static CURLcode bindlocal(struct connectdata *conn,
+                          curl_socket_t sockfd, int af)
+{
+  struct SessionHandle *data = conn->data;
+
+  struct Curl_sockaddr_storage sa;
+  struct sockaddr *sock = (struct sockaddr *)&sa;  /* bind to this address */
+  curl_socklen_t sizeof_sa = 0; /* size of the data sock points to */
+  struct sockaddr_in *si4 = (struct sockaddr_in *)&sa;
+#ifdef ENABLE_IPV6
+  struct sockaddr_in6 *si6 = (struct sockaddr_in6 *)&sa;
+#endif
+
+  struct Curl_dns_entry *h=NULL;
+  unsigned short port = data->set.localport; /* use this port number, 0 for
+                                                "random" */
+  /* how many port numbers to try to bind to, increasing one at a time */
+  int portnum = data->set.localportrange;
+  const char *dev = data->set.str[STRING_DEVICE];
+  int error;
+  char myhost[256] = "";
+  int done = 0; /* -1 for error, 1 for address found */
+  bool is_interface = FALSE;
+  bool is_host = FALSE;
+  static const char *if_prefix = "if!";
+  static const char *host_prefix = "host!";
+
+  /*************************************************************
+   * Select device to bind socket to
+   *************************************************************/
+  if(!dev && !port)
+    /* no local kind of binding was requested */
+    return CURLE_OK;
+
+  memset(&sa, 0, sizeof(struct Curl_sockaddr_storage));
+
+  if(dev && (strlen(dev)<255) ) {
+    if(strncmp(if_prefix, dev, strlen(if_prefix)) == 0) {
+      dev += strlen(if_prefix);
+      is_interface = TRUE;
+    }
+    else if(strncmp(host_prefix, dev, strlen(host_prefix)) == 0) {
+      dev += strlen(host_prefix);
+      is_host = TRUE;
+    }
+
+    /* interface */
+    if(!is_host) {
+      switch(Curl_if2ip(af, conn->scope, dev, myhost, sizeof(myhost))) {
+        case IF2IP_NOT_FOUND:
+          if(is_interface) {
+            /* Do not fall back to treating it as a host name */
+            failf(data, "Couldn't bind to interface '%s'", dev);
+            return CURLE_INTERFACE_FAILED;
+          }
+          break;
+        case IF2IP_AF_NOT_SUPPORTED:
+          /* Signal the caller to try another address family if available */
+          return CURLE_UNSUPPORTED_PROTOCOL;
+        case IF2IP_FOUND:
+          is_interface = TRUE;
+          /*
+           * We now have the numerical IP address in the 'myhost' buffer
+           */
+          infof(data, "Local Interface %s is ip %s using address family %i\n",
+                dev, myhost, af);
+          done = 1;
+
+#ifdef SO_BINDTODEVICE
+          /* I am not sure any other OSs than Linux that provide this feature,
+           * and at the least I cannot test. --Ben
+           *
+           * This feature allows one to tightly bind the local socket to a
+           * particular interface.  This will force even requests to other
+           * local interfaces to go out the external interface.
+           *
+           *
+           * Only bind to the interface when specified as interface, not just
+           * as a hostname or ip address.
+           */
+          if(setsockopt(sockfd, SOL_SOCKET, SO_BINDTODEVICE,
+                        dev, (curl_socklen_t)strlen(dev)+1) != 0) {
+            error = SOCKERRNO;
+            infof(data, "SO_BINDTODEVICE %s failed with errno %d: %s;"
+                  " will do regular bind\n",
+                  dev, error, Curl_strerror(conn, error));
+            /* This is typically "errno 1, error: Operation not permitted" if
+               you're not running as root or another suitable privileged
+               user */
+          }
+#endif
+          break;
+      }
+    }
+    if(!is_interface) {
+      /*
+       * This was not an interface, resolve the name as a host name
+       * or IP number
+       *
+       * Temporarily force name resolution to use only the address type
+       * of the connection. The resolve functions should really be changed
+       * to take a type parameter instead.
+       */
+      long ipver = conn->ip_version;
+      int rc;
+
+      if(af == AF_INET)
+        conn->ip_version = CURL_IPRESOLVE_V4;
+#ifdef ENABLE_IPV6
+      else if(af == AF_INET6)
+        conn->ip_version = CURL_IPRESOLVE_V6;
+#endif
+
+      rc = Curl_resolv(conn, dev, 0, &h);
+      if(rc == CURLRESOLV_PENDING)
+        (void)Curl_resolver_wait_resolv(conn, &h);
+      conn->ip_version = ipver;
+
+      if(h) {
+        /* convert the resolved address, sizeof myhost >= INET_ADDRSTRLEN */
+        Curl_printable_address(h->addr, myhost, sizeof(myhost));
+        infof(data, "Name '%s' family %i resolved to '%s' family %i\n",
+              dev, af, myhost, h->addr->ai_family);
+        Curl_resolv_unlock(data, h);
+        done = 1;
+      }
+      else {
+        /*
+         * provided dev was no interface (or interfaces are not supported
+         * e.g. solaris) no ip address and no domain we fail here
+         */
+        done = -1;
+      }
+    }
+
+    if(done > 0) {
+#ifdef ENABLE_IPV6
+      /* ipv6 address */
+      if(af == AF_INET6) {
+#ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID
+        char *scope_ptr = strchr(myhost, '%');
+        if(scope_ptr)
+          *(scope_ptr++) = 0;
+#endif
+        if(Curl_inet_pton(AF_INET6, myhost, &si6->sin6_addr) > 0) {
+          si6->sin6_family = AF_INET6;
+          si6->sin6_port = htons(port);
+#ifdef HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID
+          if(scope_ptr)
+            /* The "myhost" string either comes from Curl_if2ip or from
+               Curl_printable_address. The latter returns only numeric scope
+               IDs and the former returns none at all.  So the scope ID, if
+               present, is known to be numeric */
+            si6->sin6_scope_id = atoi(scope_ptr);
+#endif
+        }
+        sizeof_sa = sizeof(struct sockaddr_in6);
+      }
+      else
+#endif
+      /* ipv4 address */
+      if((af == AF_INET) &&
+         (Curl_inet_pton(AF_INET, myhost, &si4->sin_addr) > 0)) {
+        si4->sin_family = AF_INET;
+        si4->sin_port = htons(port);
+        sizeof_sa = sizeof(struct sockaddr_in);
+      }
+    }
+
+    if(done < 1) {
+      failf(data, "Couldn't bind to '%s'", dev);
+      return CURLE_INTERFACE_FAILED;
+    }
+  }
+  else {
+    /* no device was given, prepare sa to match af's needs */
+#ifdef ENABLE_IPV6
+    if(af == AF_INET6) {
+      si6->sin6_family = AF_INET6;
+      si6->sin6_port = htons(port);
+      sizeof_sa = sizeof(struct sockaddr_in6);
+    }
+    else
+#endif
+    if(af == AF_INET) {
+      si4->sin_family = AF_INET;
+      si4->sin_port = htons(port);
+      sizeof_sa = sizeof(struct sockaddr_in);
+    }
+  }
+
+  for(;;) {
+    if(bind(sockfd, sock, sizeof_sa) >= 0) {
+      /* we succeeded to bind */
+      struct Curl_sockaddr_storage add;
+      curl_socklen_t size = sizeof(add);
+      memset(&add, 0, sizeof(struct Curl_sockaddr_storage));
+      if(getsockname(sockfd, (struct sockaddr *) &add, &size) < 0) {
+        data->state.os_errno = error = SOCKERRNO;
+        failf(data, "getsockname() failed with errno %d: %s",
+              error, Curl_strerror(conn, error));
+        return CURLE_INTERFACE_FAILED;
+      }
+      infof(data, "Local port: %hu\n", port);
+      conn->bits.bound = TRUE;
+      return CURLE_OK;
+    }
+
+    if(--portnum > 0) {
+      infof(data, "Bind to local port %hu failed, trying next\n", port);
+      port++; /* try next port */
+      /* We re-use/clobber the port variable here below */
+      if(sock->sa_family == AF_INET)
+        si4->sin_port = ntohs(port);
+#ifdef ENABLE_IPV6
+      else
+        si6->sin6_port = ntohs(port);
+#endif
+    }
+    else
+      break;
+  }
+
+  data->state.os_errno = error = SOCKERRNO;
+  failf(data, "bind failed with errno %d: %s",
+        error, Curl_strerror(conn, error));
+
+  return CURLE_INTERFACE_FAILED;
+}
+
+/*
+ * verifyconnect() returns TRUE if the connect really has happened.
+ */
+static bool verifyconnect(curl_socket_t sockfd, int *error)
+{
+  bool rc = TRUE;
+#ifdef SO_ERROR
+  int err = 0;
+  curl_socklen_t errSize = sizeof(err);
+
+#ifdef WIN32
+  /*
+   * In October 2003 we effectively nullified this function on Windows due to
+   * problems with it using all CPU in multi-threaded cases.
+   *
+   * In May 2004, we bring it back to offer more info back on connect failures.
+   * Gisle Vanem could reproduce the former problems with this function, but
+   * could avoid them by adding this SleepEx() call below:
+   *
+   *    "I don't have Rational Quantify, but the hint from his post was
+   *    ntdll::NtRemoveIoCompletion(). So I'd assume the SleepEx (or maybe
+   *    just Sleep(0) would be enough?) would release whatever
+   *    mutex/critical-section the ntdll call is waiting on.
+   *
+   *    Someone got to verify this on Win-NT 4.0, 2000."
+   */
+
+#ifdef _WIN32_WCE
+  Sleep(0);
+#else
+  SleepEx(0, FALSE);
+#endif
+
+#endif
+
+  if(0 != getsockopt(sockfd, SOL_SOCKET, SO_ERROR, (void *)&err, &errSize))
+    err = SOCKERRNO;
+#ifdef _WIN32_WCE
+  /* Old WinCE versions don't support SO_ERROR */
+  if(WSAENOPROTOOPT == err) {
+    SET_SOCKERRNO(0);
+    err = 0;
+  }
+#endif
+#ifdef __minix
+  /* Minix 3.1.x doesn't support getsockopt on UDP sockets */
+  if(EBADIOCTL == err) {
+    SET_SOCKERRNO(0);
+    err = 0;
+  }
+#endif
+  if((0 == err) || (EISCONN == err))
+    /* we are connected, awesome! */
+    rc = TRUE;
+  else
+    /* This wasn't a successful connect */
+    rc = FALSE;
+  if(error)
+    *error = err;
+#else
+  (void)sockfd;
+  if(error)
+    *error = SOCKERRNO;
+#endif
+  return rc;
+}
+
+/* Used within the multi interface. Try next IP address, return TRUE if no
+   more address exists or error */
+static CURLcode trynextip(struct connectdata *conn,
+                          int sockindex,
+                          bool *connected)
+{
+  curl_socket_t sockfd;
+  Curl_addrinfo *ai;
+
+  /* First clean up after the failed socket.
+     Don't close it yet to ensure that the next IP's socket gets a different
+     file descriptor, which can prevent bugs when the curl_multi_socket_action
+     interface is used with certain select() replacements such as kqueue. */
+  curl_socket_t fd_to_close = conn->sock[sockindex];
+  conn->sock[sockindex] = CURL_SOCKET_BAD;
+  *connected = FALSE;
+
+  if(sockindex != FIRSTSOCKET) {
+    Curl_closesocket(conn, fd_to_close);
+    return CURLE_COULDNT_CONNECT; /* no next */
+  }
+
+  /* try the next address */
+  ai = conn->ip_addr->ai_next;
+
+  while(ai) {
+    CURLcode res = singleipconnect(conn, ai, &sockfd, connected);
+    if(res)
+      return res;
+    if(sockfd != CURL_SOCKET_BAD) {
+      /* store the new socket descriptor */
+      conn->sock[sockindex] = sockfd;
+      conn->ip_addr = ai;
+      Curl_closesocket(conn, fd_to_close);
+      return CURLE_OK;
+    }
+    ai = ai->ai_next;
+  }
+  Curl_closesocket(conn, fd_to_close);
+  return CURLE_COULDNT_CONNECT;
+}
+
+/* Copies connection info into the session handle to make it available
+   when the session handle is no longer associated with a connection. */
+void Curl_persistconninfo(struct connectdata *conn)
+{
+  memcpy(conn->data->info.conn_primary_ip, conn->primary_ip, MAX_IPADR_LEN);
+  memcpy(conn->data->info.conn_local_ip, conn->local_ip, MAX_IPADR_LEN);
+  conn->data->info.conn_primary_port = conn->primary_port;
+  conn->data->info.conn_local_port = conn->local_port;
+}
+
+/* retrieves ip address and port from a sockaddr structure */
+static bool getaddressinfo(struct sockaddr* sa, char* addr,
+                           long* port)
+{
+  unsigned short us_port;
+  struct sockaddr_in* si = NULL;
+#ifdef ENABLE_IPV6
+  struct sockaddr_in6* si6 = NULL;
+#endif
+#if defined(HAVE_SYS_UN_H) && defined(AF_UNIX)
+  struct sockaddr_un* su = NULL;
+#endif
+
+  switch (sa->sa_family) {
+    case AF_INET:
+      si = (struct sockaddr_in*) sa;
+      if(Curl_inet_ntop(sa->sa_family, &si->sin_addr,
+                        addr, MAX_IPADR_LEN)) {
+        us_port = ntohs(si->sin_port);
+        *port = us_port;
+        return TRUE;
+      }
+      break;
+#ifdef ENABLE_IPV6
+    case AF_INET6:
+      si6 = (struct sockaddr_in6*)sa;
+      if(Curl_inet_ntop(sa->sa_family, &si6->sin6_addr,
+                        addr, MAX_IPADR_LEN)) {
+        us_port = ntohs(si6->sin6_port);
+        *port = us_port;
+        return TRUE;
+      }
+      break;
+#endif
+#if defined(HAVE_SYS_UN_H) && defined(AF_UNIX)
+    case AF_UNIX:
+      su = (struct sockaddr_un*)sa;
+      snprintf(addr, MAX_IPADR_LEN, "%s", su->sun_path);
+      *port = 0;
+      return TRUE;
+#endif
+    default:
+      break;
+  }
+
+  addr[0] = '\0';
+  *port = 0;
+
+  return FALSE;
+}
+
+/* retrieves the start/end point information of a socket of an established
+   connection */
+void Curl_updateconninfo(struct connectdata *conn, curl_socket_t sockfd)
+{
+  int error;
+  curl_socklen_t len;
+  struct Curl_sockaddr_storage ssrem;
+  struct Curl_sockaddr_storage ssloc;
+  struct SessionHandle *data = conn->data;
+
+  if(!conn->bits.reuse) {
+
+    len = sizeof(struct Curl_sockaddr_storage);
+    if(getpeername(sockfd, (struct sockaddr*) &ssrem, &len)) {
+      error = SOCKERRNO;
+      failf(data, "getpeername() failed with errno %d: %s",
+            error, Curl_strerror(conn, error));
+      return;
+    }
+
+    len = sizeof(struct Curl_sockaddr_storage);
+    if(getsockname(sockfd, (struct sockaddr*) &ssloc, &len)) {
+      error = SOCKERRNO;
+      failf(data, "getsockname() failed with errno %d: %s",
+            error, Curl_strerror(conn, error));
+      return;
+    }
+
+    if(!getaddressinfo((struct sockaddr*)&ssrem,
+                        conn->primary_ip, &conn->primary_port)) {
+      error = ERRNO;
+      failf(data, "ssrem inet_ntop() failed with errno %d: %s",
+            error, Curl_strerror(conn, error));
+      return;
+    }
+
+    if(!getaddressinfo((struct sockaddr*)&ssloc,
+                       conn->local_ip, &conn->local_port)) {
+      error = ERRNO;
+      failf(data, "ssloc inet_ntop() failed with errno %d: %s",
+            error, Curl_strerror(conn, error));
+      return;
+    }
+
+  }
+
+  /* persist connection info in session handle */
+  Curl_persistconninfo(conn);
+}
+
+/*
+ * Curl_is_connected() checks if the socket has connected.
+ */
+
+CURLcode Curl_is_connected(struct connectdata *conn,
+                           int sockindex,
+                           bool *connected)
+{
+  struct SessionHandle *data = conn->data;
+  CURLcode code = CURLE_OK;
+  curl_socket_t sockfd = conn->sock[sockindex];
+  long allow = DEFAULT_CONNECT_TIMEOUT;
+  int error = 0;
+  struct timeval now;
+  enum chkconn_t chk;
+
+  DEBUGASSERT(sockindex >= FIRSTSOCKET && sockindex <= SECONDARYSOCKET);
+
+  *connected = FALSE; /* a very negative world view is best */
+
+  if(conn->bits.tcpconnect[sockindex]) {
+    /* we are connected already! */
+    *connected = TRUE;
+    return CURLE_OK;
+  }
+
+  now = Curl_tvnow();
+
+  /* figure out how long time we have left to connect */
+  allow = Curl_timeleft(data, &now, TRUE);
+
+  if(allow < 0) {
+    /* time-out, bail out, go home */
+    failf(data, "Connection time-out");
+    return CURLE_OPERATION_TIMEDOUT;
+  }
+
+  /* check socket for connect */
+  chk = checkconnect(sockfd);
+  if(CHKCONN_IDLE == chk) {
+    if(curlx_tvdiff(now, conn->connecttime) >= conn->timeoutms_per_addr) {
+      infof(data, "After %ldms connect time, move on!\n",
+            conn->timeoutms_per_addr);
+      goto next;
+    }
+
+    /* not an error, but also no connection yet */
+    return code;
+  }
+
+  if(CHKCONN_CONNECTED == chk) {
+    if(verifyconnect(sockfd, &error)) {
+      /* we are connected with TCP, awesome! */
+
+      /* see if we need to do any proxy magic first once we connected */
+      code = Curl_connected_proxy(conn);
+      if(code)
+        return code;
+
+      conn->bits.tcpconnect[sockindex] = TRUE;
+
+      *connected = TRUE;
+      if(sockindex == FIRSTSOCKET)
+        Curl_pgrsTime(data, TIMER_CONNECT); /* connect done */
+      Curl_verboseconnect(conn);
+      Curl_updateconninfo(conn, sockfd);
+
+      return CURLE_OK;
+    }
+    /* nope, not connected for real */
+  }
+  else {
+    /* nope, not connected  */
+    if(CHKCONN_FDSET_ERROR == chk) {
+      (void)verifyconnect(sockfd, &error);
+      infof(data, "%s\n",Curl_strerror(conn, error));
+    }
+    else
+      infof(data, "Connection failed\n");
+  }
+
+  /*
+   * The connection failed here, we should attempt to connect to the "next
+   * address" for the given host. But first remember the latest error.
+   */
+  if(error) {
+    data->state.os_errno = error;
+    SET_SOCKERRNO(error);
+  }
+  next:
+
+  conn->timeoutms_per_addr = conn->ip_addr->ai_next == NULL ?
+                             allow : allow / 2;
+  code = trynextip(conn, sockindex, connected);
+
+  if(code) {
+    error = SOCKERRNO;
+    data->state.os_errno = error;
+    failf(data, "Failed connect to %s:%ld; %s",
+          conn->host.name, conn->port, Curl_strerror(conn, error));
+  }
+
+  return code;
+}
+
+static void tcpnodelay(struct connectdata *conn,
+                       curl_socket_t sockfd)
+{
+#ifdef TCP_NODELAY
+  struct SessionHandle *data= conn->data;
+  curl_socklen_t onoff = (curl_socklen_t) data->set.tcp_nodelay;
+  int level = IPPROTO_TCP;
+
+#if 0
+  /* The use of getprotobyname() is disabled since it isn't thread-safe on
+     numerous systems. On these getprotobyname_r() should be used instead, but
+     that exists in at least one 4 arg version and one 5 arg version, and
+     since the proto number rarely changes anyway we now just use the hard
+     coded number. The "proper" fix would need a configure check for the
+     correct function much in the same style the gethostbyname_r versions are
+     detected. */
+  struct protoent *pe = getprotobyname("tcp");
+  if(pe)
+    level = pe->p_proto;
+#endif
+
+  if(setsockopt(sockfd, level, TCP_NODELAY, (void *)&onoff,
+                sizeof(onoff)) < 0)
+    infof(data, "Could not set TCP_NODELAY: %s\n",
+          Curl_strerror(conn, SOCKERRNO));
+  else
+    infof(data,"TCP_NODELAY set\n");
+#else
+  (void)conn;
+  (void)sockfd;
+#endif
+}
+
+#ifdef SO_NOSIGPIPE
+/* The preferred method on Mac OS X (10.2 and later) to prevent SIGPIPEs when
+   sending data to a dead peer (instead of relying on the 4th argument to send
+   being MSG_NOSIGNAL). Possibly also existing and in use on other BSD
+   systems? */
+static void nosigpipe(struct connectdata *conn,
+                      curl_socket_t sockfd)
+{
+  struct SessionHandle *data= conn->data;
+  int onoff = 1;
+  if(setsockopt(sockfd, SOL_SOCKET, SO_NOSIGPIPE, (void *)&onoff,
+                sizeof(onoff)) < 0)
+    infof(data, "Could not set SO_NOSIGPIPE: %s\n",
+          Curl_strerror(conn, SOCKERRNO));
+}
+#else
+#define nosigpipe(x,y) Curl_nop_stmt
+#endif
+
+#ifdef USE_WINSOCK
+/* When you run a program that uses the Windows Sockets API, you may
+   experience slow performance when you copy data to a TCP server.
+
+   http://support.microsoft.com/kb/823764
+
+   Work-around: Make the Socket Send Buffer Size Larger Than the Program Send
+   Buffer Size
+
+   The problem described in this knowledge-base is applied only to pre-Vista
+   Windows.  Following function trying to detect OS version and skips
+   SO_SNDBUF adjustment for Windows Vista and above.
+*/
+#define DETECT_OS_NONE 0
+#define DETECT_OS_PREVISTA 1
+#define DETECT_OS_VISTA_OR_LATER 2
+
+void Curl_sndbufset(curl_socket_t sockfd)
+{
+  int val = CURL_MAX_WRITE_SIZE + 32;
+  int curval = 0;
+  int curlen = sizeof(curval);
+
+  OSVERSIONINFO osver;
+  static int detectOsState = DETECT_OS_NONE;
+
+  if(detectOsState == DETECT_OS_NONE) {
+    memset(&osver, 0, sizeof(osver));
+    osver.dwOSVersionInfoSize = sizeof(osver);
+    detectOsState = DETECT_OS_PREVISTA;
+    if(GetVersionEx(&osver)) {
+      if(osver.dwMajorVersion >= 6)
+        detectOsState = DETECT_OS_VISTA_OR_LATER;
+    }
+  }
+  if(detectOsState == DETECT_OS_VISTA_OR_LATER)
+    return;
+
+  if(getsockopt(sockfd, SOL_SOCKET, SO_SNDBUF, (char *)&curval, &curlen) == 0)
+    if(curval > val)
+      return;
+
+  setsockopt(sockfd, SOL_SOCKET, SO_SNDBUF, (const char *)&val, sizeof(val));
+}
+#endif
+
+
+/*
+ * singleipconnect()
+ *
+ * Note that even on connect fail it returns CURLE_OK, but with 'sock' set to
+ * CURL_SOCKET_BAD. Other errors will however return proper errors.
+ *
+ * singleipconnect() connects to the given IP only, and it may return without
+ * having connected.
+ */
+static CURLcode
+singleipconnect(struct connectdata *conn,
+                const Curl_addrinfo *ai,
+                curl_socket_t *sockp,
+                bool *connected)
+{
+  struct Curl_sockaddr_ex addr;
+  int rc;
+  int error = 0;
+  bool isconnected = FALSE;
+  struct SessionHandle *data = conn->data;
+  curl_socket_t sockfd;
+  CURLcode res = CURLE_OK;
+
+  *sockp = CURL_SOCKET_BAD;
+  *connected = FALSE; /* default is not connected */
+
+  res = Curl_socket(conn, ai, &addr, &sockfd);
+  if(res)
+    /* Failed to create the socket, but still return OK since we signal the
+       lack of socket as well. This allows the parent function to keep looping
+       over alternative addresses/socket families etc. */
+    return CURLE_OK;
+
+  /* store remote address and port used in this connection attempt */
+  if(!getaddressinfo((struct sockaddr*)&addr.sa_addr,
+                     conn->primary_ip, &conn->primary_port)) {
+    /* malformed address or bug in inet_ntop, try next address */
+    error = ERRNO;
+    failf(data, "sa_addr inet_ntop() failed with errno %d: %s",
+          error, Curl_strerror(conn, error));
+    Curl_closesocket(conn, sockfd);
+    return CURLE_OK;
+  }
+  memcpy(conn->ip_addr_str, conn->primary_ip, MAX_IPADR_LEN);
+  infof(data, "  Trying %s...\n", conn->ip_addr_str);
+
+  Curl_persistconninfo(conn);
+
+  if(data->set.tcp_nodelay)
+    tcpnodelay(conn, sockfd);
+
+  nosigpipe(conn, sockfd);
+
+  Curl_sndbufset(sockfd);
+
+  if(data->set.tcp_keepalive)
+    tcpkeepalive(data, sockfd);
+
+  if(data->set.fsockopt) {
+    /* activate callback for setting socket options */
+    error = data->set.fsockopt(data->set.sockopt_client,
+                               sockfd,
+                               CURLSOCKTYPE_IPCXN);
+
+    if(error == CURL_SOCKOPT_ALREADY_CONNECTED)
+      isconnected = TRUE;
+    else if(error) {
+      Curl_closesocket(conn, sockfd); /* close the socket and bail out */
+      return CURLE_ABORTED_BY_CALLBACK;
+    }
+  }
+
+  /* possibly bind the local end to an IP, interface or port */
+  res = bindlocal(conn, sockfd, addr.family);
+  if(res) {
+    Curl_closesocket(conn, sockfd); /* close socket and bail out */
+    if(res == CURLE_UNSUPPORTED_PROTOCOL) {
+      /* The address family is not supported on this interface.
+         We can continue trying addresses */
+      return CURLE_OK;
+    }
+    return res;
+  }
+
+  /* set socket non-blocking */
+  curlx_nonblock(sockfd, TRUE);
+
+  conn->connecttime = Curl_tvnow();
+  if(conn->num_addr > 1)
+    Curl_expire(data, conn->timeoutms_per_addr);
+
+  /* Connect TCP sockets, bind UDP */
+  if(!isconnected && (conn->socktype == SOCK_STREAM)) {
+    rc = connect(sockfd, &addr.sa_addr, addr.addrlen);
+    if(-1 == rc)
+      error = SOCKERRNO;
+  }
+  else {
+    *sockp = sockfd;
+    return CURLE_OK;
+  }
+
+#ifdef ENABLE_IPV6
+  conn->bits.ipv6 = (addr.family == AF_INET6)?TRUE:FALSE;
+#endif
+
+  if(-1 == rc) {
+    switch (error) {
+    case EINPROGRESS:
+    case EWOULDBLOCK:
+#if defined(EAGAIN)
+#if (EAGAIN) != (EWOULDBLOCK)
+      /* On some platforms EAGAIN and EWOULDBLOCK are the
+       * same value, and on others they are different, hence
+       * the odd #if
+       */
+    case EAGAIN:
+#endif
+#endif
+      *sockp = sockfd;
+      return CURLE_OK;
+
+    default:
+      /* unknown error, fallthrough and try another address! */
+      failf(data, "Failed to connect to %s: %s",
+            conn->ip_addr_str, Curl_strerror(conn,error));
+      data->state.os_errno = error;
+
+      /* connect failed */
+      Curl_closesocket(conn, sockfd);
+
+      break;
+    }
+  }
+  else
+    *sockp = sockfd;
+
+  return CURLE_OK;
+}
+
+/*
+ * TCP connect to the given host with timeout, proxy or remote doesn't matter.
+ * There might be more than one IP address to try out. Fill in the passed
+ * pointer with the connected socket.
+ */
+
+CURLcode Curl_connecthost(struct connectdata *conn,  /* context */
+                          const struct Curl_dns_entry *remotehost,
+                          curl_socket_t *sockconn,   /* the connected socket */
+                          Curl_addrinfo **addr,      /* the one we used */
+                          bool *connected)           /* really connected? */
+{
+  struct SessionHandle *data = conn->data;
+  curl_socket_t sockfd = CURL_SOCKET_BAD;
+  Curl_addrinfo *ai;
+  Curl_addrinfo *curr_addr;
+
+  struct timeval after;
+  struct timeval before = Curl_tvnow();
+
+  /*************************************************************
+   * Figure out what maximum time we have left
+   *************************************************************/
+  long timeout_ms;
+
+  DEBUGASSERT(sockconn);
+  *connected = FALSE; /* default to not connected */
+
+  /* get the timeout left */
+  timeout_ms = Curl_timeleft(data, &before, TRUE);
+
+  if(timeout_ms < 0) {
+    /* a precaution, no need to continue if time already is up */
+    failf(data, "Connection time-out");
+    return CURLE_OPERATION_TIMEDOUT;
+  }
+
+  conn->num_addr = Curl_num_addresses(remotehost->addr);
+
+  ai = remotehost->addr;
+
+  /* Below is the loop that attempts to connect to all IP-addresses we
+   * know for the given host. One by one until one IP succeeds.
+   */
+
+  /*
+   * Connecting with a Curl_addrinfo chain
+   */
+  for(curr_addr = ai; curr_addr; curr_addr = curr_addr->ai_next) {
+    CURLcode res;
+
+    /* Max time for the next address */
+    conn->timeoutms_per_addr = curr_addr->ai_next == NULL ?
+                               timeout_ms : timeout_ms / 2;
+
+    /* start connecting to the IP curr_addr points to */
+    res = singleipconnect(conn, curr_addr,
+                          &sockfd, connected);
+    if(res)
+      return res;
+
+    if(sockfd != CURL_SOCKET_BAD)
+      break;
+
+    /* get a new timeout for next attempt */
+    after = Curl_tvnow();
+    timeout_ms -= Curl_tvdiff(after, before);
+    if(timeout_ms < 0) {
+      failf(data, "connect() timed out!");
+      return CURLE_OPERATION_TIMEDOUT;
+    }
+    before = after;
+  }  /* end of connect-to-each-address loop */
+
+  *sockconn = sockfd;    /* the socket descriptor we've connected */
+
+  if(sockfd == CURL_SOCKET_BAD) {
+    /* no good connect was made */
+    failf(data, "couldn't connect to %s at %s:%ld",
+          conn->bits.proxy?"proxy":"host",
+          conn->bits.proxy?conn->proxy.name:conn->host.name, conn->port);
+    return CURLE_COULDNT_CONNECT;
+  }
+
+  /* leave the socket in non-blocking mode */
+
+  /* store the address we use */
+  if(addr)
+    *addr = curr_addr;
+
+  data->info.numconnects++; /* to track the number of connections made */
+
+  return CURLE_OK;
+}
+
+struct connfind {
+  struct connectdata *tofind;
+  bool found;
+};
+
+static int conn_is_conn(struct connectdata *conn, void *param)
+{
+  struct connfind *f = (struct connfind *)param;
+  if(conn == f->tofind) {
+    f->found = TRUE;
+    return 1;
+  }
+  return 0;
+}
+
+/*
+ * Used to extract socket and connectdata struct for the most recent
+ * transfer on the given SessionHandle.
+ *
+ * The returned socket will be CURL_SOCKET_BAD in case of failure!
+ */
+curl_socket_t Curl_getconnectinfo(struct SessionHandle *data,
+                                  struct connectdata **connp)
+{
+  curl_socket_t sockfd;
+
+  DEBUGASSERT(data);
+
+  /* this only works for an easy handle that has been used for
+     curl_easy_perform()! */
+  if(data->state.lastconnect && data->multi_easy) {
+    struct connectdata *c = data->state.lastconnect;
+    struct connfind find;
+    find.tofind = data->state.lastconnect;
+    find.found = FALSE;
+
+    Curl_conncache_foreach(data->multi_easy->conn_cache, &find, conn_is_conn);
+
+    if(!find.found) {
+      data->state.lastconnect = NULL;
+      return CURL_SOCKET_BAD;
+    }
+
+    if(connp)
+      /* only store this if the caller cares for it */
+      *connp = c;
+    sockfd = c->sock[FIRSTSOCKET];
+    /* we have a socket connected, let's determine if the server shut down */
+    /* determine if ssl */
+    if(c->ssl[FIRSTSOCKET].use) {
+      /* use the SSL context */
+      if(!Curl_ssl_check_cxn(c))
+        return CURL_SOCKET_BAD;   /* FIN received */
+    }
+/* Minix 3.1 doesn't support any flags on recv; just assume socket is OK */
+#ifdef MSG_PEEK
+    else {
+      /* use the socket */
+      char buf;
+      if(recv((RECV_TYPE_ARG1)c->sock[FIRSTSOCKET], (RECV_TYPE_ARG2)&buf,
+              (RECV_TYPE_ARG3)1, (RECV_TYPE_ARG4)MSG_PEEK) == 0) {
+        return CURL_SOCKET_BAD;   /* FIN received */
+      }
+    }
+#endif
+  }
+  else
+    return CURL_SOCKET_BAD;
+
+  return sockfd;
+}
+
+/*
+ * Close a socket.
+ *
+ * 'conn' can be NULL, beware!
+ */
+int Curl_closesocket(struct connectdata *conn,
+                      curl_socket_t sock)
+{
+  if(conn && conn->fclosesocket) {
+    if((sock == conn->sock[SECONDARYSOCKET]) &&
+       conn->sock_accepted[SECONDARYSOCKET])
+      /* if this socket matches the second socket, and that was created with
+         accept, then we MUST NOT call the callback but clear the accepted
+         status */
+      conn->sock_accepted[SECONDARYSOCKET] = FALSE;
+    else
+      return conn->fclosesocket(conn->closesocket_client, sock);
+  }
+  sclose(sock);
+
+  if(conn)
+    /* tell the multi-socket code about this */
+    Curl_multi_closed(conn, sock);
+
+  return 0;
+}
+
+/*
+ * Create a socket based on info from 'conn' and 'ai'.
+ *
+ * 'addr' should be a pointer to the correct struct to get data back, or NULL.
+ * 'sockfd' must be a pointer to a socket descriptor.
+ *
+ * If the open socket callback is set, used that!
+ *
+ */
+CURLcode Curl_socket(struct connectdata *conn,
+                     const Curl_addrinfo *ai,
+                     struct Curl_sockaddr_ex *addr,
+                     curl_socket_t *sockfd)
+{
+  struct SessionHandle *data = conn->data;
+  struct Curl_sockaddr_ex dummy;
+
+  if(!addr)
+    /* if the caller doesn't want info back, use a local temp copy */
+    addr = &dummy;
+
+  /*
+   * The Curl_sockaddr_ex structure is basically libcurl's external API
+   * curl_sockaddr structure with enough space available to directly hold
+   * any protocol-specific address structures. The variable declared here
+   * will be used to pass / receive data to/from the fopensocket callback
+   * if this has been set, before that, it is initialized from parameters.
+   */
+
+  addr->family = ai->ai_family;
+  addr->socktype = conn->socktype;
+  addr->protocol = conn->socktype==SOCK_DGRAM?IPPROTO_UDP:ai->ai_protocol;
+  addr->addrlen = ai->ai_addrlen;
+
+  if(addr->addrlen > sizeof(struct Curl_sockaddr_storage))
+     addr->addrlen = sizeof(struct Curl_sockaddr_storage);
+  memcpy(&addr->sa_addr, ai->ai_addr, addr->addrlen);
+
+  if(data->set.fopensocket)
+   /*
+    * If the opensocket callback is set, all the destination address
+    * information is passed to the callback. Depending on this information the
+    * callback may opt to abort the connection, this is indicated returning
+    * CURL_SOCKET_BAD; otherwise it will return a not-connected socket. When
+    * the callback returns a valid socket the destination address information
+    * might have been changed and this 'new' address will actually be used
+    * here to connect.
+    */
+    *sockfd = data->set.fopensocket(data->set.opensocket_client,
+                                    CURLSOCKTYPE_IPCXN,
+                                    (struct curl_sockaddr *)addr);
+  else
+    /* opensocket callback not set, so simply create the socket now */
+    *sockfd = socket(addr->family, addr->socktype, addr->protocol);
+
+  if(*sockfd == CURL_SOCKET_BAD)
+    /* no socket, no connection */
+    return CURLE_COULDNT_CONNECT;
+
+#if defined(ENABLE_IPV6) && defined(HAVE_SOCKADDR_IN6_SIN6_SCOPE_ID)
+  if(conn->scope && (addr->family == AF_INET6)) {
+    struct sockaddr_in6 * const sa6 = (void *)&addr->sa_addr;
+    sa6->sin6_scope_id = conn->scope;
+  }
+#endif
+
+  return CURLE_OK;
+
+}