mirror of
https://github.com/moparisthebest/wget
synced 2024-07-03 16:38:41 -04:00
965 lines
27 KiB
C
965 lines
27 KiB
C
/* Establishing and handling network connections.
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Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
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2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
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This file is part of GNU Wget.
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GNU Wget is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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||
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GNU Wget is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with Wget. If not, see <http://www.gnu.org/licenses/>.
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Additional permission under GNU GPL version 3 section 7
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If you modify this program, or any covered work, by linking or
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||
combining it with the OpenSSL project's OpenSSL library (or a
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||
modified version of that library), containing parts covered by the
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||
terms of the OpenSSL or SSLeay licenses, the Free Software Foundation
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||
grants you additional permission to convey the resulting work.
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Corresponding Source for a non-source form of such a combination
|
||
shall include the source code for the parts of OpenSSL used as well
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as that of the covered work. */
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#include "wget.h"
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#include <stdio.h>
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#include <stdlib.h>
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#ifdef HAVE_UNISTD_H
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# include <unistd.h>
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#endif
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#include <assert.h>
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#ifndef WINDOWS
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# include <sys/socket.h>
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# include <netdb.h>
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# include <netinet/in.h>
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# ifndef __BEOS__
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# include <arpa/inet.h>
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# endif
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#endif /* not WINDOWS */
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#include <errno.h>
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#include <string.h>
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#ifdef HAVE_SYS_SELECT_H
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# include <sys/select.h>
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#endif /* HAVE_SYS_SELECT_H */
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#ifdef HAVE_SYS_TIME_H
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# include <sys/time.h>
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#endif
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#include "utils.h"
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#include "host.h"
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#include "connect.h"
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#include "hash.h"
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||
/* Define sockaddr_storage where unavailable (presumably on IPv4-only
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hosts). */
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#ifndef ENABLE_IPV6
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# ifndef HAVE_STRUCT_SOCKADDR_STORAGE
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# define sockaddr_storage sockaddr_in
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# endif
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#endif /* ENABLE_IPV6 */
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/* Fill SA as per the data in IP and PORT. SA shoult point to struct
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sockaddr_storage if ENABLE_IPV6 is defined, to struct sockaddr_in
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otherwise. */
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static void
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sockaddr_set_data (struct sockaddr *sa, const ip_address *ip, int port)
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{
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switch (ip->family)
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{
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||
case AF_INET:
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{
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struct sockaddr_in *sin = (struct sockaddr_in *)sa;
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xzero (*sin);
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sin->sin_family = AF_INET;
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sin->sin_port = htons (port);
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sin->sin_addr = ip->data.d4;
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break;
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}
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#ifdef ENABLE_IPV6
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case AF_INET6:
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{
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struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sa;
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xzero (*sin6);
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sin6->sin6_family = AF_INET6;
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sin6->sin6_port = htons (port);
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sin6->sin6_addr = ip->data.d6;
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#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
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sin6->sin6_scope_id = ip->ipv6_scope;
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#endif
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break;
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}
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#endif /* ENABLE_IPV6 */
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default:
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abort ();
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}
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}
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/* Get the data of SA, specifically the IP address and the port. If
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you're not interested in one or the other information, pass NULL as
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the pointer. */
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static void
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sockaddr_get_data (const struct sockaddr *sa, ip_address *ip, int *port)
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{
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||
switch (sa->sa_family)
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{
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case AF_INET:
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{
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struct sockaddr_in *sin = (struct sockaddr_in *)sa;
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if (ip)
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{
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ip->family = AF_INET;
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ip->data.d4 = sin->sin_addr;
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}
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if (port)
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*port = ntohs (sin->sin_port);
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break;
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}
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#ifdef ENABLE_IPV6
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case AF_INET6:
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{
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struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sa;
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if (ip)
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{
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||
ip->family = AF_INET6;
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ip->data.d6 = sin6->sin6_addr;
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#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
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ip->ipv6_scope = sin6->sin6_scope_id;
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#endif
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}
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if (port)
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*port = ntohs (sin6->sin6_port);
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break;
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}
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#endif
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default:
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abort ();
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||
}
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||
}
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||
/* Return the size of the sockaddr structure depending on its
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family. */
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||
static socklen_t
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sockaddr_size (const struct sockaddr *sa)
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{
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switch (sa->sa_family)
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{
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case AF_INET:
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return sizeof (struct sockaddr_in);
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#ifdef ENABLE_IPV6
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case AF_INET6:
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return sizeof (struct sockaddr_in6);
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#endif
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default:
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abort ();
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}
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}
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/* Resolve the bind address specified via --bind-address and store it
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to SA. The resolved value is stored in a static variable and
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reused after the first invocation of this function.
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Returns true on success, false on failure. */
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static bool
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resolve_bind_address (struct sockaddr *sa)
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{
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struct address_list *al;
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/* Make sure this is called only once. opt.bind_address doesn't
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change during a Wget run. */
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static bool called, should_bind;
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static ip_address ip;
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if (called)
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{
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if (should_bind)
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sockaddr_set_data (sa, &ip, 0);
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return should_bind;
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}
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called = true;
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al = lookup_host (opt.bind_address, LH_BIND | LH_SILENT);
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if (!al)
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{
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/* #### We should be able to print the error message here. */
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logprintf (LOG_NOTQUIET,
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_("%s: unable to resolve bind address %s; disabling bind.\n"),
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exec_name, quote (opt.bind_address));
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should_bind = false;
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return false;
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}
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/* Pick the first address in the list and use it as bind address.
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Perhaps we should try multiple addresses in succession, but I
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don't think that's necessary in practice. */
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ip = *address_list_address_at (al, 0);
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address_list_release (al);
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sockaddr_set_data (sa, &ip, 0);
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should_bind = true;
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return true;
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}
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struct cwt_context {
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int fd;
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const struct sockaddr *addr;
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socklen_t addrlen;
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int result;
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};
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static void
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connect_with_timeout_callback (void *arg)
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{
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struct cwt_context *ctx = (struct cwt_context *)arg;
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ctx->result = connect (ctx->fd, ctx->addr, ctx->addrlen);
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}
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/* Like connect, but specifies a timeout. If connecting takes longer
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than TIMEOUT seconds, -1 is returned and errno is set to
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ETIMEDOUT. */
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static int
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connect_with_timeout (int fd, const struct sockaddr *addr, socklen_t addrlen,
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double timeout)
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{
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struct cwt_context ctx;
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ctx.fd = fd;
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ctx.addr = addr;
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ctx.addrlen = addrlen;
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if (run_with_timeout (timeout, connect_with_timeout_callback, &ctx))
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{
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errno = ETIMEDOUT;
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return -1;
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}
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if (ctx.result == -1 && errno == EINTR)
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errno = ETIMEDOUT;
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return ctx.result;
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}
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/* Connect via TCP to the specified address and port.
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If PRINT is non-NULL, it is the host name to print that we're
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connecting to. */
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int
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connect_to_ip (const ip_address *ip, int port, const char *print)
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{
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struct sockaddr_storage ss;
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struct sockaddr *sa = (struct sockaddr *)&ss;
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int sock;
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/* If PRINT is non-NULL, print the "Connecting to..." line, with
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PRINT being the host name we're connecting to. */
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if (print)
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{
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const char *txt_addr = print_address (ip);
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if (print && 0 != strcmp (print, txt_addr))
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logprintf (LOG_VERBOSE, _("Connecting to %s|%s|:%d... "),
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escnonprint_uri (print), txt_addr, port);
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else
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logprintf (LOG_VERBOSE, _("Connecting to %s:%d... "), txt_addr, port);
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}
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/* Store the sockaddr info to SA. */
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sockaddr_set_data (sa, ip, port);
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/* Create the socket of the family appropriate for the address. */
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sock = socket (sa->sa_family, SOCK_STREAM, 0);
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if (sock < 0)
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goto err;
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#if defined(ENABLE_IPV6) && defined(IPV6_V6ONLY)
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if (opt.ipv6_only) {
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int on = 1;
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/* In case of error, we will go on anyway... */
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int err = setsockopt (sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof (on));
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IF_DEBUG
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if (err < 0)
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DEBUGP (("Failed setting IPV6_V6ONLY: %s", strerror (errno)));
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}
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#endif
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/* For very small rate limits, set the buffer size (and hence,
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hopefully, the kernel's TCP window size) to the per-second limit.
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That way we should never have to sleep for more than 1s between
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network reads. */
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if (opt.limit_rate && opt.limit_rate < 8192)
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{
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int bufsize = opt.limit_rate;
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if (bufsize < 512)
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bufsize = 512; /* avoid pathologically small values */
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#ifdef SO_RCVBUF
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setsockopt (sock, SOL_SOCKET, SO_RCVBUF,
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(void *)&bufsize, (socklen_t)sizeof (bufsize));
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#endif
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/* When we add limit_rate support for writing, which is useful
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for POST, we should also set SO_SNDBUF here. */
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}
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if (opt.bind_address)
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{
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/* Bind the client side of the socket to the requested
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address. */
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struct sockaddr_storage bind_ss;
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struct sockaddr *bind_sa = (struct sockaddr *)&bind_ss;
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if (resolve_bind_address (bind_sa))
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{
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if (bind (sock, bind_sa, sockaddr_size (bind_sa)) < 0)
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goto err;
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}
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}
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/* Connect the socket to the remote endpoint. */
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if (connect_with_timeout (sock, sa, sockaddr_size (sa),
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opt.connect_timeout) < 0)
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goto err;
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/* Success. */
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assert (sock >= 0);
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if (print)
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logprintf (LOG_VERBOSE, _("connected.\n"));
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DEBUGP (("Created socket %d.\n", sock));
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return sock;
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err:
|
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{
|
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/* Protect errno from possible modifications by close and
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logprintf. */
|
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int save_errno = errno;
|
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if (sock >= 0)
|
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fd_close (sock);
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if (print)
|
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logprintf (LOG_VERBOSE, _("failed: %s.\n"), strerror (errno));
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errno = save_errno;
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return -1;
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}
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}
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/* Connect via TCP to a remote host on the specified port.
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HOST is resolved as an Internet host name. If HOST resolves to
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more than one IP address, they are tried in the order returned by
|
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DNS until connecting to one of them succeeds. */
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int
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connect_to_host (const char *host, int port)
|
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{
|
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int i, start, end;
|
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int sock;
|
||
|
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struct address_list *al = lookup_host (host, 0);
|
||
|
||
retry:
|
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if (!al)
|
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{
|
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logprintf (LOG_NOTQUIET,
|
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_("%s: unable to resolve host address %s\n"),
|
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exec_name, quote (host));
|
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return E_HOST;
|
||
}
|
||
|
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address_list_get_bounds (al, &start, &end);
|
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for (i = start; i < end; i++)
|
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{
|
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const ip_address *ip = address_list_address_at (al, i);
|
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sock = connect_to_ip (ip, port, host);
|
||
if (sock >= 0)
|
||
{
|
||
/* Success. */
|
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address_list_set_connected (al);
|
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address_list_release (al);
|
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return sock;
|
||
}
|
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|
||
/* The attempt to connect has failed. Continue with the loop
|
||
and try next address. */
|
||
|
||
address_list_set_faulty (al, i);
|
||
}
|
||
|
||
/* Failed to connect to any of the addresses in AL. */
|
||
|
||
if (address_list_connected_p (al))
|
||
{
|
||
/* We connected to AL before, but cannot do so now. That might
|
||
indicate that our DNS cache entry for HOST has expired. */
|
||
address_list_release (al);
|
||
al = lookup_host (host, LH_REFRESH);
|
||
goto retry;
|
||
}
|
||
address_list_release (al);
|
||
|
||
return -1;
|
||
}
|
||
|
||
/* Create a socket, bind it to local interface BIND_ADDRESS on port
|
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*PORT, set up a listen backlog, and return the resulting socket, or
|
||
-1 in case of error.
|
||
|
||
BIND_ADDRESS is the address of the interface to bind to. If it is
|
||
NULL, the socket is bound to the default address. PORT should
|
||
point to the port number that will be used for the binding. If
|
||
that number is 0, the system will choose a suitable port, and the
|
||
chosen value will be written to *PORT.
|
||
|
||
Calling accept() on such a socket waits for and accepts incoming
|
||
TCP connections. */
|
||
|
||
int
|
||
bind_local (const ip_address *bind_address, int *port)
|
||
{
|
||
int sock;
|
||
struct sockaddr_storage ss;
|
||
struct sockaddr *sa = (struct sockaddr *)&ss;
|
||
|
||
/* For setting options with setsockopt. */
|
||
int setopt_val = 1;
|
||
void *setopt_ptr = (void *)&setopt_val;
|
||
socklen_t setopt_size = sizeof (setopt_val);
|
||
|
||
sock = socket (bind_address->family, SOCK_STREAM, 0);
|
||
if (sock < 0)
|
||
return -1;
|
||
|
||
#ifdef SO_REUSEADDR
|
||
setsockopt (sock, SOL_SOCKET, SO_REUSEADDR, setopt_ptr, setopt_size);
|
||
#endif
|
||
|
||
xzero (ss);
|
||
sockaddr_set_data (sa, bind_address, *port);
|
||
if (bind (sock, sa, sockaddr_size (sa)) < 0)
|
||
{
|
||
fd_close (sock);
|
||
return -1;
|
||
}
|
||
DEBUGP (("Local socket fd %d bound.\n", sock));
|
||
|
||
/* If *PORT is 0, find out which port we've bound to. */
|
||
if (*port == 0)
|
||
{
|
||
socklen_t addrlen = sockaddr_size (sa);
|
||
if (getsockname (sock, sa, &addrlen) < 0)
|
||
{
|
||
/* If we can't find out the socket's local address ("name"),
|
||
something is seriously wrong with the socket, and it's
|
||
unusable for us anyway because we must know the chosen
|
||
port. */
|
||
fd_close (sock);
|
||
return -1;
|
||
}
|
||
sockaddr_get_data (sa, NULL, port);
|
||
DEBUGP (("binding to address %s using port %i.\n",
|
||
print_address (bind_address), *port));
|
||
}
|
||
if (listen (sock, 1) < 0)
|
||
{
|
||
fd_close (sock);
|
||
return -1;
|
||
}
|
||
return sock;
|
||
}
|
||
|
||
/* Like a call to accept(), but with the added check for timeout.
|
||
|
||
In other words, accept a client connection on LOCAL_SOCK, and
|
||
return the new socket used for communication with the client.
|
||
LOCAL_SOCK should have been bound, e.g. using bind_local().
|
||
|
||
The caller is blocked until a connection is established. If no
|
||
connection is established for opt.connect_timeout seconds, the
|
||
function exits with an error status. */
|
||
|
||
int
|
||
accept_connection (int local_sock)
|
||
{
|
||
int sock;
|
||
|
||
/* We don't need the values provided by accept, but accept
|
||
apparently requires them to be present. */
|
||
struct sockaddr_storage ss;
|
||
struct sockaddr *sa = (struct sockaddr *)&ss;
|
||
socklen_t addrlen = sizeof (ss);
|
||
|
||
if (opt.connect_timeout)
|
||
{
|
||
int test = select_fd (local_sock, opt.connect_timeout, WAIT_FOR_READ);
|
||
if (test == 0)
|
||
errno = ETIMEDOUT;
|
||
if (test <= 0)
|
||
return -1;
|
||
}
|
||
sock = accept (local_sock, sa, &addrlen);
|
||
DEBUGP (("Accepted client at socket %d.\n", sock));
|
||
return sock;
|
||
}
|
||
|
||
/* Get the IP address associated with the connection on FD and store
|
||
it to IP. Return true on success, false otherwise.
|
||
|
||
If ENDPOINT is ENDPOINT_LOCAL, it returns the address of the local
|
||
(client) side of the socket. Else if ENDPOINT is ENDPOINT_PEER, it
|
||
returns the address of the remote (peer's) side of the socket. */
|
||
|
||
bool
|
||
socket_ip_address (int sock, ip_address *ip, int endpoint)
|
||
{
|
||
struct sockaddr_storage storage;
|
||
struct sockaddr *sockaddr = (struct sockaddr *)&storage;
|
||
socklen_t addrlen = sizeof (storage);
|
||
int ret;
|
||
|
||
if (endpoint == ENDPOINT_LOCAL)
|
||
ret = getsockname (sock, sockaddr, &addrlen);
|
||
else if (endpoint == ENDPOINT_PEER)
|
||
ret = getpeername (sock, sockaddr, &addrlen);
|
||
else
|
||
abort ();
|
||
if (ret < 0)
|
||
return false;
|
||
|
||
ip->family = sockaddr->sa_family;
|
||
switch (sockaddr->sa_family)
|
||
{
|
||
#ifdef ENABLE_IPV6
|
||
case AF_INET6:
|
||
{
|
||
struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)&storage;
|
||
ip->data.d6 = sa6->sin6_addr;
|
||
#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
|
||
ip->ipv6_scope = sa6->sin6_scope_id;
|
||
#endif
|
||
DEBUGP (("conaddr is: %s\n", print_address (ip)));
|
||
return true;
|
||
}
|
||
#endif
|
||
case AF_INET:
|
||
{
|
||
struct sockaddr_in *sa = (struct sockaddr_in *)&storage;
|
||
ip->data.d4 = sa->sin_addr;
|
||
DEBUGP (("conaddr is: %s\n", print_address (ip)));
|
||
return true;
|
||
}
|
||
default:
|
||
abort ();
|
||
}
|
||
}
|
||
|
||
/* Return true if the error from the connect code can be considered
|
||
retryable. Wget normally retries after errors, but the exception
|
||
are the "unsupported protocol" type errors (possible on IPv4/IPv6
|
||
dual family systems) and "connection refused". */
|
||
|
||
bool
|
||
retryable_socket_connect_error (int err)
|
||
{
|
||
/* Have to guard against some of these values not being defined.
|
||
Cannot use a switch statement because some of the values might be
|
||
equal. */
|
||
if (false
|
||
#ifdef EAFNOSUPPORT
|
||
|| err == EAFNOSUPPORT
|
||
#endif
|
||
#ifdef EPFNOSUPPORT
|
||
|| err == EPFNOSUPPORT
|
||
#endif
|
||
#ifdef ESOCKTNOSUPPORT /* no, "sockt" is not a typo! */
|
||
|| err == ESOCKTNOSUPPORT
|
||
#endif
|
||
#ifdef EPROTONOSUPPORT
|
||
|| err == EPROTONOSUPPORT
|
||
#endif
|
||
#ifdef ENOPROTOOPT
|
||
|| err == ENOPROTOOPT
|
||
#endif
|
||
/* Apparently, older versions of Linux and BSD used EINVAL
|
||
instead of EAFNOSUPPORT and such. */
|
||
|| err == EINVAL
|
||
)
|
||
return false;
|
||
|
||
if (!opt.retry_connrefused)
|
||
if (err == ECONNREFUSED
|
||
#ifdef ENETUNREACH
|
||
|| err == ENETUNREACH /* network is unreachable */
|
||
#endif
|
||
#ifdef EHOSTUNREACH
|
||
|| err == EHOSTUNREACH /* host is unreachable */
|
||
#endif
|
||
)
|
||
return false;
|
||
|
||
return true;
|
||
}
|
||
|
||
/* Wait for a single descriptor to become available, timing out after
|
||
MAXTIME seconds. Returns 1 if FD is available, 0 for timeout and
|
||
-1 for error. The argument WAIT_FOR can be a combination of
|
||
WAIT_FOR_READ and WAIT_FOR_WRITE.
|
||
|
||
This is a mere convenience wrapper around the select call, and
|
||
should be taken as such (for example, it doesn't implement Wget's
|
||
0-timeout-means-no-timeout semantics.) */
|
||
|
||
int
|
||
select_fd (int fd, double maxtime, int wait_for)
|
||
{
|
||
fd_set fdset;
|
||
fd_set *rd = NULL, *wr = NULL;
|
||
struct timeval tmout;
|
||
int result;
|
||
|
||
FD_ZERO (&fdset);
|
||
FD_SET (fd, &fdset);
|
||
if (wait_for & WAIT_FOR_READ)
|
||
rd = &fdset;
|
||
if (wait_for & WAIT_FOR_WRITE)
|
||
wr = &fdset;
|
||
|
||
tmout.tv_sec = (long) maxtime;
|
||
tmout.tv_usec = 1000000 * (maxtime - (long) maxtime);
|
||
|
||
do
|
||
result = select (fd + 1, rd, wr, NULL, &tmout);
|
||
while (result < 0 && errno == EINTR);
|
||
|
||
return result;
|
||
}
|
||
|
||
/* Return true iff the connection to the remote site established
|
||
through SOCK is still open.
|
||
|
||
Specifically, this function returns true if SOCK is not ready for
|
||
reading. This is because, when the connection closes, the socket
|
||
is ready for reading because EOF is about to be delivered. A side
|
||
effect of this method is that sockets that have pending data are
|
||
considered non-open. This is actually a good thing for callers of
|
||
this function, where such pending data can only be unwanted
|
||
leftover from a previous request. */
|
||
|
||
bool
|
||
test_socket_open (int sock)
|
||
{
|
||
fd_set check_set;
|
||
struct timeval to;
|
||
|
||
/* Check if we still have a valid (non-EOF) connection. From Andrew
|
||
* Maholski's code in the Unix Socket FAQ. */
|
||
|
||
FD_ZERO (&check_set);
|
||
FD_SET (sock, &check_set);
|
||
|
||
/* Wait one microsecond */
|
||
to.tv_sec = 0;
|
||
to.tv_usec = 1;
|
||
|
||
if (select (sock + 1, &check_set, NULL, NULL, &to) == 0)
|
||
/* We got a timeout, it means we're still connected. */
|
||
return true;
|
||
else
|
||
/* Read now would not wait, it means we have either pending data
|
||
or EOF/error. */
|
||
return false;
|
||
}
|
||
|
||
/* Basic socket operations, mostly EINTR wrappers. */
|
||
|
||
#if defined(WINDOWS) || defined(MSDOS)
|
||
# define read(fd, buf, cnt) recv (fd, buf, cnt, 0)
|
||
# define write(fd, buf, cnt) send (fd, buf, cnt, 0)
|
||
# define close(fd) closesocket (fd)
|
||
#endif
|
||
|
||
#ifdef __BEOS__
|
||
# define read(fd, buf, cnt) recv (fd, buf, cnt, 0)
|
||
# define write(fd, buf, cnt) send (fd, buf, cnt, 0)
|
||
#endif
|
||
|
||
static int
|
||
sock_read (int fd, char *buf, int bufsize)
|
||
{
|
||
int res;
|
||
do
|
||
res = read (fd, buf, bufsize);
|
||
while (res == -1 && errno == EINTR);
|
||
return res;
|
||
}
|
||
|
||
static int
|
||
sock_write (int fd, char *buf, int bufsize)
|
||
{
|
||
int res;
|
||
do
|
||
res = write (fd, buf, bufsize);
|
||
while (res == -1 && errno == EINTR);
|
||
return res;
|
||
}
|
||
|
||
static int
|
||
sock_poll (int fd, double timeout, int wait_for)
|
||
{
|
||
return select_fd (fd, timeout, wait_for);
|
||
}
|
||
|
||
static int
|
||
sock_peek (int fd, char *buf, int bufsize)
|
||
{
|
||
int res;
|
||
do
|
||
res = recv (fd, buf, bufsize, MSG_PEEK);
|
||
while (res == -1 && errno == EINTR);
|
||
return res;
|
||
}
|
||
|
||
static void
|
||
sock_close (int fd)
|
||
{
|
||
close (fd);
|
||
DEBUGP (("Closed fd %d\n", fd));
|
||
}
|
||
#undef read
|
||
#undef write
|
||
#undef close
|
||
|
||
/* Reading and writing from the network. We build around the socket
|
||
(file descriptor) API, but support "extended" operations for things
|
||
that are not mere file descriptors under the hood, such as SSL
|
||
sockets.
|
||
|
||
That way the user code can call fd_read(fd, ...) and we'll run read
|
||
or SSL_read or whatever is necessary. */
|
||
|
||
static struct hash_table *transport_map;
|
||
static unsigned int transport_map_modified_tick;
|
||
|
||
struct transport_info {
|
||
struct transport_implementation *imp;
|
||
void *ctx;
|
||
};
|
||
|
||
/* Register the transport layer operations that will be used when
|
||
reading, writing, and polling FD.
|
||
|
||
This should be used for transport layers like SSL that piggyback on
|
||
sockets. FD should otherwise be a real socket, on which you can
|
||
call getpeername, etc. */
|
||
|
||
void
|
||
fd_register_transport (int fd, struct transport_implementation *imp, void *ctx)
|
||
{
|
||
struct transport_info *info;
|
||
|
||
/* The file descriptor must be non-negative to be registered.
|
||
Negative values are ignored by fd_close(), and -1 cannot be used as
|
||
hash key. */
|
||
assert (fd >= 0);
|
||
|
||
info = xnew (struct transport_info);
|
||
info->imp = imp;
|
||
info->ctx = ctx;
|
||
if (!transport_map)
|
||
transport_map = hash_table_new (0, NULL, NULL);
|
||
hash_table_put (transport_map, (void *)(intptr_t) fd, info);
|
||
++transport_map_modified_tick;
|
||
}
|
||
|
||
/* Return context of the transport registered with
|
||
fd_register_transport. This assumes fd_register_transport was
|
||
previously called on FD. */
|
||
|
||
void *
|
||
fd_transport_context (int fd)
|
||
{
|
||
struct transport_info *info = hash_table_get (transport_map, (void *)(intptr_t) fd);
|
||
return info->ctx;
|
||
}
|
||
|
||
/* When fd_read/fd_write are called multiple times in a loop, they should
|
||
remember the INFO pointer instead of fetching it every time. It is
|
||
not enough to compare FD to LAST_FD because FD might have been
|
||
closed and reopened. modified_tick ensures that changes to
|
||
transport_map will not be unnoticed.
|
||
|
||
This is a macro because we want the static storage variables to be
|
||
per-function. */
|
||
|
||
#define LAZY_RETRIEVE_INFO(info) do { \
|
||
static struct transport_info *last_info; \
|
||
static int last_fd = -1; \
|
||
static unsigned int last_tick; \
|
||
if (!transport_map) \
|
||
info = NULL; \
|
||
else if (last_fd == fd && last_tick == transport_map_modified_tick) \
|
||
info = last_info; \
|
||
else \
|
||
{ \
|
||
info = hash_table_get (transport_map, (void *)(intptr_t) fd); \
|
||
last_fd = fd; \
|
||
last_info = info; \
|
||
last_tick = transport_map_modified_tick; \
|
||
} \
|
||
} while (0)
|
||
|
||
static bool
|
||
poll_internal (int fd, struct transport_info *info, int wf, double timeout)
|
||
{
|
||
if (timeout == -1)
|
||
timeout = opt.read_timeout;
|
||
if (timeout)
|
||
{
|
||
int test;
|
||
if (info && info->imp->poller)
|
||
test = info->imp->poller (fd, timeout, wf, info->ctx);
|
||
else
|
||
test = sock_poll (fd, timeout, wf);
|
||
if (test == 0)
|
||
errno = ETIMEDOUT;
|
||
if (test <= 0)
|
||
return false;
|
||
}
|
||
return true;
|
||
}
|
||
|
||
/* Read no more than BUFSIZE bytes of data from FD, storing them to
|
||
BUF. If TIMEOUT is non-zero, the operation aborts if no data is
|
||
received after that many seconds. If TIMEOUT is -1, the value of
|
||
opt.timeout is used for TIMEOUT. */
|
||
|
||
int
|
||
fd_read (int fd, char *buf, int bufsize, double timeout)
|
||
{
|
||
struct transport_info *info;
|
||
LAZY_RETRIEVE_INFO (info);
|
||
if (!poll_internal (fd, info, WAIT_FOR_READ, timeout))
|
||
return -1;
|
||
if (info && info->imp->reader)
|
||
return info->imp->reader (fd, buf, bufsize, info->ctx);
|
||
else
|
||
return sock_read (fd, buf, bufsize);
|
||
}
|
||
|
||
/* Like fd_read, except it provides a "preview" of the data that will
|
||
be read by subsequent calls to fd_read. Specifically, it copies no
|
||
more than BUFSIZE bytes of the currently available data to BUF and
|
||
returns the number of bytes copied. Return values and timeout
|
||
semantics are the same as those of fd_read.
|
||
|
||
CAVEAT: Do not assume that the first subsequent call to fd_read
|
||
will retrieve the same amount of data. Reading can return more or
|
||
less data, depending on the TCP implementation and other
|
||
circumstances. However, barring an error, it can be expected that
|
||
all the peeked data will eventually be read by fd_read. */
|
||
|
||
int
|
||
fd_peek (int fd, char *buf, int bufsize, double timeout)
|
||
{
|
||
struct transport_info *info;
|
||
LAZY_RETRIEVE_INFO (info);
|
||
if (!poll_internal (fd, info, WAIT_FOR_READ, timeout))
|
||
return -1;
|
||
if (info && info->imp->peeker)
|
||
return info->imp->peeker (fd, buf, bufsize, info->ctx);
|
||
else
|
||
return sock_peek (fd, buf, bufsize);
|
||
}
|
||
|
||
/* Write the entire contents of BUF to FD. If TIMEOUT is non-zero,
|
||
the operation aborts if no data is received after that many
|
||
seconds. If TIMEOUT is -1, the value of opt.timeout is used for
|
||
TIMEOUT. */
|
||
|
||
int
|
||
fd_write (int fd, char *buf, int bufsize, double timeout)
|
||
{
|
||
int res;
|
||
struct transport_info *info;
|
||
LAZY_RETRIEVE_INFO (info);
|
||
|
||
/* `write' may write less than LEN bytes, thus the loop keeps trying
|
||
it until all was written, or an error occurred. */
|
||
res = 0;
|
||
while (bufsize > 0)
|
||
{
|
||
if (!poll_internal (fd, info, WAIT_FOR_WRITE, timeout))
|
||
return -1;
|
||
if (info && info->imp->writer)
|
||
res = info->imp->writer (fd, buf, bufsize, info->ctx);
|
||
else
|
||
res = sock_write (fd, buf, bufsize);
|
||
if (res <= 0)
|
||
break;
|
||
buf += res;
|
||
bufsize -= res;
|
||
}
|
||
return res;
|
||
}
|
||
|
||
/* Report the most recent error(s) on FD. This should only be called
|
||
after fd_* functions, such as fd_read and fd_write, and only if
|
||
they return a negative result. For errors coming from other calls
|
||
such as setsockopt or fopen, strerror should continue to be
|
||
used.
|
||
|
||
If the transport doesn't support error messages or doesn't supply
|
||
one, strerror(errno) is returned. The returned error message
|
||
should not be used after fd_close has been called. */
|
||
|
||
const char *
|
||
fd_errstr (int fd)
|
||
{
|
||
/* Don't bother with LAZY_RETRIEVE_INFO, as this will only be called
|
||
in case of error, never in a tight loop. */
|
||
struct transport_info *info = NULL;
|
||
if (transport_map)
|
||
info = hash_table_get (transport_map, (void *)(intptr_t) fd);
|
||
|
||
if (info && info->imp->errstr)
|
||
{
|
||
const char *err = info->imp->errstr (fd, info->ctx);
|
||
if (err)
|
||
return err;
|
||
/* else, fall through and print the system error. */
|
||
}
|
||
return strerror (errno);
|
||
}
|
||
|
||
/* Close the file descriptor FD. */
|
||
|
||
void
|
||
fd_close (int fd)
|
||
{
|
||
struct transport_info *info;
|
||
if (fd < 0)
|
||
return;
|
||
|
||
/* Don't use LAZY_RETRIEVE_INFO because fd_close() is only called once
|
||
per socket, so that particular optimization wouldn't work. */
|
||
info = NULL;
|
||
if (transport_map)
|
||
info = hash_table_get (transport_map, (void *)(intptr_t) fd);
|
||
|
||
if (info && info->imp->closer)
|
||
info->imp->closer (fd, info->ctx);
|
||
else
|
||
sock_close (fd);
|
||
|
||
if (info)
|
||
{
|
||
hash_table_remove (transport_map, (void *)(intptr_t) fd);
|
||
xfree (info);
|
||
++transport_map_modified_tick;
|
||
}
|
||
}
|