curl/lib/connect.c
Daniel Stenberg 5c52cacc98 - Frank Ticheler provided a patch that fixes how libcurl connects to multiple
addresses, if one of them fails (ipv4-code).
2003-10-08 13:32:43 +00:00

744 lines
20 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2003, 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.
*
* $Id$
***************************************************************************/
#include "setup.h"
#ifndef WIN32
/* headers for non-win32 */
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef HAVE_STDLIB_H
#include <stdlib.h> /* required for free() prototype, without it, this crashes
on macos 68K */
#endif
#ifdef VMS
#include <in.h>
#include <inet.h>
#endif
#endif
#include <stdio.h>
#include <errno.h>
#include <string.h>
#ifndef TRUE
#define TRUE 1
#define FALSE 0
#endif
#ifdef WIN32
#define HAVE_IOCTLSOCKET
#include <windows.h>
#include <winsock.h>
#define EINPROGRESS WSAEINPROGRESS
#define EWOULDBLOCK WSAEWOULDBLOCK
#define EISCONN WSAEISCONN
#define ENOTSOCK WSAENOTSOCK
#endif
#include "urldata.h"
#include "sendf.h"
#include "if2ip.h"
/* The last #include file should be: */
#ifdef CURLDEBUG
#include "memdebug.h"
#endif
int Curl_ourerrno(void)
{
#ifdef WIN32
return (int)GetLastError();
#else
return errno;
#endif
}
/*************************************************************************
* Curl_nonblock
*
* Description:
* Set the socket to either blocking or non-blocking mode.
*/
int Curl_nonblock(int socket, /* operate on this */
int nonblock /* TRUE or FALSE */)
{
#undef SETBLOCK
#ifdef HAVE_O_NONBLOCK
/* most recent unix versions */
int flags;
flags = fcntl(socket, F_GETFL, 0);
if (TRUE == nonblock)
return fcntl(socket, F_SETFL, flags | O_NONBLOCK);
else
return fcntl(socket, F_SETFL, flags & (~O_NONBLOCK));
#define SETBLOCK 1
#endif
#ifdef HAVE_FIONBIO
/* older unix versions */
int flags;
flags = nonblock;
return ioctl(socket, FIONBIO, &flags);
#define SETBLOCK 2
#endif
#ifdef HAVE_IOCTLSOCKET
/* Windows? */
int flags;
flags = nonblock;
return ioctlsocket(socket, FIONBIO, &flags);
#define SETBLOCK 3
#endif
#ifdef HAVE_IOCTLSOCKET_CASE
/* presumably for Amiga */
return IoctlSocket(socket, FIONBIO, (long)nonblock);
#define SETBLOCK 4
#endif
#ifdef HAVE_SO_NONBLOCK
/* BeOS */
long b = nonblock ? 1 : 0;
return setsockopt(socket, SOL_SOCKET, SO_NONBLOCK, &b, sizeof(b));
#define SETBLOCK 5
#endif
#ifdef HAVE_DISABLED_NONBLOCKING
return 0; /* returns success */
#define SETBLOCK 6
#endif
#ifndef SETBLOCK
#error "no non-blocking method was found/used/set"
#endif
}
/*
* waitconnect() returns:
* 0 fine connect
* -1 select() error
* 1 select() timeout
* 2 select() returned with an error condition
*/
static
int waitconnect(int sockfd, /* socket */
int timeout_msec)
{
fd_set fd;
fd_set errfd;
struct timeval interval;
int rc;
/* now select() until we get connect or timeout */
FD_ZERO(&fd);
FD_SET(sockfd, &fd);
FD_ZERO(&errfd);
FD_SET(sockfd, &errfd);
interval.tv_sec = timeout_msec/1000;
timeout_msec -= interval.tv_sec*1000;
interval.tv_usec = timeout_msec*1000;
rc = select(sockfd+1, NULL, &fd, &errfd, &interval);
if(-1 == rc)
/* error, no connect here, try next */
return -1;
else if(0 == rc)
/* timeout, no connect today */
return 1;
if(FD_ISSET(sockfd, &errfd))
/* error condition caught */
return 2;
/* we have a connect! */
return 0;
}
static CURLcode bindlocal(struct connectdata *conn,
int sockfd)
{
#ifdef HAVE_INET_NTOA
struct SessionHandle *data = conn->data;
/*************************************************************
* Select device to bind socket to
*************************************************************/
if (strlen(data->set.device)<255) {
struct sockaddr_in sa;
struct Curl_dns_entry *h=NULL;
size_t size;
char myhost[256] = "";
in_addr_t in;
int rc;
/* First check if the given name is an IP address */
in=inet_addr(data->set.device);
if((in == CURL_INADDR_NONE) &&
Curl_if2ip(data->set.device, myhost, sizeof(myhost))) {
/*
* We now have the numerical IPv4-style x.y.z.w in the 'myhost' buffer
*/
rc = Curl_resolv(conn, myhost, 0, &h);
if(rc == 1)
rc = Curl_wait_for_resolv(conn, &h);
}
else {
if(strlen(data->set.device)>1) {
/*
* This was not an interface, resolve the name as a host name
* or IP number
*/
rc = Curl_resolv(conn, data->set.device, 0, &h);
if(rc == 1)
rc = Curl_wait_for_resolv(conn, &h);
if(h)
/* we know data->set.device is shorter than the myhost array */
strcpy(myhost, data->set.device);
}
}
if(! *myhost) {
/* need to fix this
h=Curl_gethost(data,
getmyhost(*myhost,sizeof(myhost)),
hostent_buf,
sizeof(hostent_buf));
*/
return CURLE_HTTP_PORT_FAILED;
}
infof(data, "We bind local end to %s\n", myhost);
in=inet_addr(myhost);
if (CURL_INADDR_NONE != in) {
if ( h ) {
Curl_addrinfo *addr = h->addr;
Curl_resolv_unlock(data, h);
/* we don't need it anymore after this function has returned */
#ifdef ENABLE_IPV6
(void)sa; /* prevent compiler warning */
if( bind(sockfd, addr->ai_addr, addr->ai_addrlen) >= 0) {
/* we succeeded to bind */
struct sockaddr_in6 add;
size = sizeof(add);
if(getsockname(sockfd, (struct sockaddr *) &add,
(socklen_t *)&size)<0) {
failf(data, "getsockname() failed");
return CURLE_HTTP_PORT_FAILED;
}
}
#else
memset((char *)&sa, 0, sizeof(sa));
memcpy((char *)&sa.sin_addr, addr->h_addr, addr->h_length);
sa.sin_family = AF_INET;
sa.sin_addr.s_addr = in;
sa.sin_port = 0; /* get any port */
if( bind(sockfd, (struct sockaddr *)&sa, sizeof(sa)) >= 0) {
/* we succeeded to bind */
struct sockaddr_in add;
size = sizeof(add);
if(getsockname(sockfd, (struct sockaddr *) &add,
(socklen_t *)&size)<0) {
failf(data, "getsockname() failed");
return CURLE_HTTP_PORT_FAILED;
}
}
#endif
else {
switch(errno) {
case EBADF:
failf(data, "Invalid descriptor: %d", errno);
break;
case EINVAL:
failf(data, "Invalid request: %d", errno);
break;
case EACCES:
failf(data, "Address is protected, user not superuser: %d", errno);
break;
case ENOTSOCK:
failf(data,
"Argument is a descriptor for a file, not a socket: %d",
errno);
break;
case EFAULT:
failf(data, "Inaccessable memory error: %d", errno);
break;
case ENAMETOOLONG:
failf(data, "Address too long: %d", errno);
break;
case ENOMEM:
failf(data, "Insufficient kernel memory was available: %d", errno);
break;
default:
failf(data, "errno %d", errno);
break;
} /* end of switch(errno) */
return CURLE_HTTP_PORT_FAILED;
} /* end of else */
} /* end of if h */
else {
failf(data,"could't find my own IP address (%s)", myhost);
return CURLE_HTTP_PORT_FAILED;
}
} /* end of inet_addr */
else {
failf(data, "could't find my own IP address (%s)", myhost);
return CURLE_HTTP_PORT_FAILED;
}
return CURLE_OK;
} /* end of device selection support */
#endif /* end of HAVE_INET_NTOA */
return CURLE_HTTP_PORT_FAILED;
}
static
int socketerror(int sockfd)
{
int err = 0;
socklen_t errSize = sizeof(err);
#ifdef SO_ERROR
if( -1 == getsockopt(sockfd, SOL_SOCKET, SO_ERROR,
(void *)&err, &errSize))
err = Curl_ourerrno();
#endif
return err;
}
/*
* Curl_is_connected() is used from the multi interface to check if the
* firstsocket has connected.
*/
CURLcode Curl_is_connected(struct connectdata *conn,
int sockfd,
bool *connected)
{
int rc;
struct SessionHandle *data = conn->data;
*connected = FALSE; /* a very negative world view is best */
if(data->set.timeout || data->set.connecttimeout) {
/* there is a timeout set */
/* Evaluate in milliseconds how much time that has passed */
long has_passed = Curl_tvdiff(Curl_tvnow(), data->progress.start);
/* subtract the most strict timeout of the ones */
if(data->set.timeout && data->set.connecttimeout) {
if (data->set.timeout < data->set.connecttimeout)
has_passed -= data->set.timeout*1000;
else
has_passed -= data->set.connecttimeout*1000;
}
else if(data->set.timeout)
has_passed -= data->set.timeout*1000;
else
has_passed -= data->set.connecttimeout*1000;
if(has_passed > 0 ) {
/* time-out, bail out, go home */
failf(data, "Connection time-out");
return CURLE_OPERATION_TIMEOUTED;
}
}
if(conn->bits.tcpconnect) {
/* we are connected already! */
*connected = TRUE;
return CURLE_OK;
}
/* check for connect without timeout as we want to return immediately */
rc = waitconnect(sockfd, 0);
if(0 == rc) {
int err = socketerror(sockfd);
if ((0 == err) || (EISCONN == err)) {
/* we are connected, awesome! */
*connected = TRUE;
return CURLE_OK;
}
/* nope, not connected for real */
failf(data, "Connection failed, socket error: %d", err);
return CURLE_COULDNT_CONNECT;
}
else if(1 != rc) {
int error = Curl_ourerrno();
failf(data, "Failed connect to %s:%d, errno: %d",
conn->hostname, conn->port, error);
return CURLE_COULDNT_CONNECT;
}
/*
* If the connection phase is "done" here, we should attempt to connect
* to the "next address" in the Curl_hostaddr structure that we resolved
* before. But we don't have that struct around anymore and we can't just
* keep a pointer since the cache might in fact have gotten pruned by the
* time we want to read this... Alas, we don't do this yet.
*/
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 */
struct Curl_dns_entry *remotehost, /* use this one */
int port, /* connect to this */
int *sockconn, /* the connected socket */
Curl_ipconnect **addr, /* the one we used */
bool *connected) /* really connected? */
{
struct SessionHandle *data = conn->data;
int rc;
int sockfd=-1;
int aliasindex=0;
char *hostname;
struct timeval after;
struct timeval before = Curl_tvnow();
/*************************************************************
* Figure out what maximum time we have left
*************************************************************/
long timeout_ms=300000; /* milliseconds, default to five minutes */
*connected = FALSE; /* default to not connected */
if(data->set.timeout || data->set.connecttimeout) {
double has_passed;
/* Evaluate in milliseconds how much time that has passed */
has_passed = Curl_tvdiff(Curl_tvnow(), data->progress.start);
#ifndef min
#define min(a, b) ((a) < (b) ? (a) : (b))
#endif
/* get the most strict timeout of the ones converted to milliseconds */
if(data->set.timeout && data->set.connecttimeout) {
if (data->set.timeout < data->set.connecttimeout)
timeout_ms = data->set.timeout*1000;
else
timeout_ms = data->set.connecttimeout*1000;
}
else if(data->set.timeout)
timeout_ms = data->set.timeout*1000;
else
timeout_ms = data->set.connecttimeout*1000;
/* subtract the passed time */
timeout_ms -= (long)has_passed;
if(timeout_ms < 0) {
/* a precaution, no need to continue if time already is up */
failf(data, "Connection time-out");
return CURLE_OPERATION_TIMEOUTED;
}
}
hostname = data->change.proxy?conn->proxyhost:conn->hostname;
infof(data, "About to connect() to %s%s%s:%d\n",
conn->bits.ipv6_ip?"[":"",
hostname,
conn->bits.ipv6_ip?"]":"",
port);
#ifdef ENABLE_IPV6
/*
* Connecting with IPv6 support is so much easier and cleanly done
*/
{
struct addrinfo *ai;
port =0; /* prevent compiler warning */
for (ai = remotehost->addr; ai; ai = ai->ai_next, aliasindex++) {
sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
if (sockfd < 0)
continue;
if(conn->data->set.device) {
/* user selected to bind the outgoing socket to a specified "device"
before doing connect */
CURLcode res = bindlocal(conn, sockfd);
if(res)
return res;
}
/* set socket non-blocking */
Curl_nonblock(sockfd, TRUE);
rc = connect(sockfd, ai->ai_addr, ai->ai_addrlen);
if(-1 == rc) {
int error=Curl_ourerrno();
switch (error) {
case EINPROGRESS:
case EWOULDBLOCK:
#if defined(EAGAIN) && 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
case EINTR:
/* asynchronous connect, wait for connect or timeout */
if(data->state.used_interface == Curl_if_multi)
/* don't hang when doing multi */
timeout_ms = 0;
rc = waitconnect(sockfd, timeout_ms);
break;
case ECONNREFUSED: /* no one listening */
default:
/* unknown error, fallthrough and try another address! */
failf(data, "Failed connect to %s: %d", hostname, error);
break;
}
}
if(0 == rc) {
/* we might be connected, if the socket says it is OK! Ask it! */
int err;
err = socketerror(sockfd);
if ((0 == err) || (EISCONN == err)) {
/* we are connected, awesome! */
*connected = TRUE; /* this is truly a connect */
break;
}
failf(data, "socket error: %d", err);
/* we are _not_ connected, it was a false alert, continue please */
}
else if(2 == rc)
/* waitconnect() returned error */
;
else if(data->state.used_interface == Curl_if_multi) {
/* When running the multi interface, we bail out here */
rc = 0;
break;
}
/* connect failed or timed out */
sclose(sockfd);
sockfd = -1;
/* 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_TIMEOUTED;
}
before = after;
continue;
}
if (sockfd < 0)
return CURLE_COULDNT_CONNECT;
/* leave the socket in non-blocking mode */
if(addr)
*addr = ai; /* the address we ended up connected to */
}
#else
/*
* Connecting with IPv4-only support
*/
if(!remotehost->addr->h_addr_list[0]) {
/* If there is no addresses in the address list, then we return
error right away */
failf(data, "no address available");
return CURLE_COULDNT_CONNECT;
}
/* This is the loop that attempts to connect to all IP-addresses we
know for the given host. One by one. */
for(rc=-1, aliasindex=0;
rc && (struct in_addr *)remotehost->addr->h_addr_list[aliasindex];
aliasindex++) {
struct sockaddr_in serv_addr;
/* create an IPv4 TCP socket */
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if(-1 == sockfd) {
failf(data, "couldn't create socket");
return CURLE_COULDNT_CONNECT; /* big time error */
}
if(conn->data->set.device) {
/* user selected to bind the outgoing socket to a specified "device"
before doing connect */
CURLcode res = bindlocal(conn, sockfd);
if(res)
return res;
}
/* Convert socket to non-blocking type */
Curl_nonblock(sockfd, TRUE);
/* do this nasty work to do the connect */
memset((char *) &serv_addr, '\0', sizeof(serv_addr));
memcpy((char *)&(serv_addr.sin_addr),
(struct in_addr *)remotehost->addr->h_addr_list[aliasindex],
sizeof(struct in_addr));
serv_addr.sin_family = remotehost->addr->h_addrtype;
serv_addr.sin_port = htons((unsigned short)port);
rc = connect(sockfd, (struct sockaddr *)&serv_addr,
sizeof(serv_addr));
if(-1 == rc) {
int error=Curl_ourerrno();
switch (error) {
case EINPROGRESS:
case EWOULDBLOCK:
#if defined(EAGAIN) && 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
/* asynchronous connect, wait for connect or timeout */
if(data->state.used_interface == Curl_if_multi)
/* don't hang when doing multi */
timeout_ms = 0;
rc = waitconnect(sockfd, timeout_ms);
break;
default:
/* unknown error, fallthrough and try another address! */
failf(data, "Failed to connect to %s IP number %d: %d",
hostname, aliasindex+1, error);
break;
}
}
/* The '1 == rc' comes from the waitconnect(), and not from connect().
We can be sure of this since connect() cannot return 1. */
if((1 == rc) && (data->state.used_interface == Curl_if_multi)) {
/* Timeout when running the multi interface, we return here with a
CURLE_OK return code. */
rc = 0;
break;
}
if(0 == rc) {
int err = socketerror(sockfd);
if ((0 == err) || (EISCONN == err)) {
/* we are connected, awesome! */
*connected = TRUE; /* this is a true connect */
break;
}
/* nope, not connected for real */
rc = -1;
}
if(0 != rc) {
/* get a new timeout for next attempt */
sclose(sockfd);
after = Curl_tvnow();
timeout_ms -= Curl_tvdiff(after, before);
if(timeout_ms < 0) {
failf(data, "Connect timeout on IP number %d", aliasindex+1);
break;
}
before = after;
continue; /* try next address */
}
break;
}
if(0 != rc) {
/* no good connect was made */
*sockconn = -1;
failf(data, "Connect failed");
return CURLE_COULDNT_CONNECT;
}
/* leave the socket in non-blocking mode */
if(addr)
/* this is the address we've connected to */
*addr = (struct in_addr *)remotehost->addr->h_addr_list[aliasindex];
#endif
/* allow NULL-pointers to get passed in */
if(sockconn)
*sockconn = sockfd; /* the socket descriptor we've connected */
return CURLE_OK;
}