1 /* Establishing and handling network connections.
2 Copyright (C) 1995, 1996, 1997, 2001, 2002 Free Software Foundation, Inc.
4 This file is part of GNU Wget.
6 GNU Wget is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 GNU Wget is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with Wget; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 In addition, as a special exception, the Free Software Foundation
21 gives permission to link the code of its release of Wget with the
22 OpenSSL project's "OpenSSL" library (or with modified versions of it
23 that use the same license as the "OpenSSL" library), and distribute
24 the linked executables. You must obey the GNU General Public License
25 in all respects for all of the code used other than "OpenSSL". If you
26 modify this file, you may extend this exception to your version of the
27 file, but you are not obligated to do so. If you do not wish to do
28 so, delete this exception statement from your version. */
34 #include <sys/types.h>
43 # include <sys/socket.h>
45 # include <netinet/in.h>
47 # include <arpa/inet.h>
56 #endif /* HAVE_STRING_H */
57 #ifdef HAVE_SYS_SELECT_H
58 # include <sys/select.h>
59 #endif /* HAVE_SYS_SELECT_H */
70 /* Variables shared by bindport and acceptport: */
71 static int msock = -1;
72 static struct sockaddr *addr;
74 static ip_address bind_address;
75 static int bind_address_resolved;
78 resolve_bind_address (void)
80 struct address_list *al;
82 if (bind_address_resolved || opt.bind_address == NULL)
86 al = lookup_host (opt.bind_address, 1);
89 logprintf (LOG_NOTQUIET,
90 _("Unable to convert `%s' to a bind address. Reverting to ANY.\n"),
95 address_list_copy_one (al, 0, &bind_address);
96 address_list_release (al);
97 bind_address_resolved = 1;
102 const struct sockaddr *addr;
108 connect_with_timeout_callback (void *arg)
110 struct cwt_context *ctx = (struct cwt_context *)arg;
111 ctx->result = connect (ctx->fd, ctx->addr, ctx->addrlen);
114 /* Like connect, but specifies a timeout. If connecting takes longer
115 than TIMEOUT seconds, -1 is returned and errno is set to
119 connect_with_timeout (int fd, const struct sockaddr *addr, int addrlen,
122 struct cwt_context ctx;
125 ctx.addrlen = addrlen;
127 if (run_with_timeout (timeout, connect_with_timeout_callback, &ctx))
132 if (ctx.result == -1 && errno == EINTR)
137 /* A kludge, but still better than passing the host name all the way
138 to connect_to_one. */
139 static const char *connection_host_name;
142 set_connection_host_name (const char *host)
145 assert (connection_host_name == NULL);
147 assert (connection_host_name != NULL);
149 connection_host_name = host;
152 /* Connect to a remote host whose address has been resolved. */
154 connect_to_one (ip_address *addr, unsigned short port, int silent)
157 int sock, save_errno;
159 /* Set port and protocol */
160 wget_sockaddr_set_address (&sa, ip_default_family, port, addr);
164 char *pretty_addr = pretty_print_address (addr);
165 if (connection_host_name
166 && 0 != strcmp (connection_host_name, pretty_addr))
167 logprintf (LOG_VERBOSE, _("Connecting to %s[%s]:%hu... "),
168 connection_host_name, pretty_addr, port);
170 logprintf (LOG_VERBOSE, _("Connecting to %s:%hu... "),
174 /* Make an internet socket, stream type. */
175 sock = socket (ip_default_family, SOCK_STREAM, 0);
179 /* For very small rate limits, set the buffer size (and hence,
180 hopefully, the size of the kernel window) to the size of the
181 limit. That way we don't sleep for more than 1s between network
183 if (opt.limit_rate && opt.limit_rate < 8192)
185 int bufsize = opt.limit_rate;
189 setsockopt (sock, SOL_SOCKET, SO_RCVBUF,
190 (char *)&bufsize, sizeof (bufsize));
192 /* When we add opt.limit_rate support for writing, as with
193 `--post-file', also set SO_SNDBUF here. */
196 resolve_bind_address ();
197 if (bind_address_resolved)
199 /* Bind the client side to the requested address. */
201 wget_sockaddr_set_address (&bsa, ip_default_family, 0, &bind_address);
202 if (bind (sock, &bsa.sa, sockaddr_len ()))
210 /* Connect the socket to the remote host. */
211 if (connect_with_timeout (sock, &sa.sa, sockaddr_len (),
212 opt.connect_timeout) < 0)
224 logprintf (LOG_VERBOSE, _("connected.\n"));
225 DEBUGP (("Created socket %d.\n", sock));
231 logprintf (LOG_VERBOSE, "failed: %s.\n", strerror (errno));
238 /* Connect to a remote host whose address has been resolved. */
240 connect_to_many (struct address_list *al, unsigned short port, int silent)
244 address_list_get_bounds (al, &start, &end);
245 for (i = start; i < end; i++)
249 address_list_copy_one (al, i, &addr);
251 sock = connect_to_one (&addr, port, silent);
256 address_list_set_faulty (al, i);
258 /* The attempt to connect has failed. Continue with the loop
259 and try next address. */
266 test_socket_open (int sock)
272 /* Check if we still have a valid (non-EOF) connection. From Andrew
273 * Maholski's code in the Unix Socket FAQ. */
275 FD_ZERO (&check_set);
276 FD_SET (sock, &check_set);
278 /* Wait one microsecond */
282 /* If we get a timeout, then that means still connected */
283 if (select (sock + 1, &check_set, NULL, NULL, &to) == 0)
285 /* Connection is valid (not EOF), so continue */
291 /* Without select, it's hard to know for sure. */
296 /* Bind the local port PORT. This does all the necessary work, which
297 is creating a socket, setting SO_REUSEADDR option on it, then
298 calling bind() and listen(). If *PORT is 0, a random port is
299 chosen by the system, and its value is stored to *PORT. The
300 internal variable MPORT is set to the value of the ensuing master
301 socket. Call acceptport() to block for and accept a connection. */
303 bindport (unsigned short *port, int family)
307 memset (&srv, 0, sizeof (wget_sockaddr));
311 if ((msock = socket (family, SOCK_STREAM, 0)) < 0)
315 if (setsockopt (msock, SOL_SOCKET, SO_REUSEADDR,
316 (char *)&optval, sizeof (optval)) < 0)
320 resolve_bind_address ();
321 wget_sockaddr_set_address (&srv, ip_default_family, htons (*port),
322 bind_address_resolved ? &bind_address : NULL);
323 if (bind (msock, &srv.sa, sockaddr_len ()) < 0)
329 DEBUGP (("Master socket fd %d bound.\n", msock));
332 /* #### addrlen should be a 32-bit type, which int is not
333 guaranteed to be. Oh, and don't try to make it a size_t,
334 because that can be 64-bit. */
335 int sa_len = sockaddr_len ();
336 if (getsockname (msock, &srv.sa, &sa_len) < 0)
342 *port = wget_sockaddr_get_port (&srv);
343 DEBUGP (("using port %i.\n", *port));
345 if (listen (msock, 1) < 0)
355 /* Wait for file descriptor FD to be available, timing out after
356 MAXTIME seconds. "Available" means readable if writep is 0,
359 Returns 1 if FD is available, 0 for timeout and -1 for error. */
362 select_fd (int fd, double maxtime, int writep)
365 fd_set *rd = NULL, *wrt = NULL;
366 struct timeval tmout;
371 *(writep ? &wrt : &rd) = &fds;
373 tmout.tv_sec = (long)maxtime;
374 tmout.tv_usec = 1000000L * (maxtime - (long)maxtime);
377 result = select (fd + 1, rd, wrt, NULL, &tmout);
378 while (result < 0 && errno == EINTR);
380 /* When we've timed out, set errno to ETIMEDOUT for the convenience
387 #endif /* HAVE_SELECT */
389 /* Call accept() on MSOCK and store the result to *SOCK. This assumes
390 that bindport() has been used to initialize MSOCK to a correct
391 value. It blocks the caller until a connection is established. If
392 no connection is established for OPT.CONNECT_TIMEOUT seconds, the
393 function exits with an error status. */
395 acceptport (int *sock)
397 int addrlen = sockaddr_len ();
400 if (select_fd (msock, opt.connect_timeout, 0) <= 0)
403 if ((*sock = accept (msock, addr, &addrlen)) < 0)
405 DEBUGP (("Created socket fd %d.\n", *sock));
409 /* Close SOCK, as well as the most recently remembered MSOCK, created
410 via bindport(). If SOCK is -1, close MSOCK only. */
414 /*shutdown (sock, 2);*/
422 /* Return the local IP address associated with the connection on FD. */
425 conaddr (int fd, ip_address *ip)
429 /* see bindport() for discussion of using `int' here. */
430 int addrlen = sizeof (mysrv);
432 if (getsockname (fd, &mysrv.sa, (int *)&addrlen) < 0)
435 switch (mysrv.sa.sa_family)
439 memcpy (ip, &mysrv.sin6.sin6_addr, 16);
443 map_ipv4_to_ip ((ip4_address *)&mysrv.sin.sin_addr, ip);
451 /* Read at most LEN bytes from FD, storing them to BUF. This is
452 virtually the same as read(), but takes care of EINTR braindamage
453 and uses select() to timeout the stale connections (a connection is
454 stale if more than OPT.READ_TIMEOUT time is spent in select() or
458 iread (int fd, char *buf, int len)
463 if (opt.read_timeout)
464 if (select_fd (fd, opt.read_timeout, 0) <= 0)
468 res = READ (fd, buf, len);
469 while (res == -1 && errno == EINTR);
474 /* Write LEN bytes from BUF to FD. This is similar to iread(), but
475 unlike iread(), it makes sure that all of BUF is actually written
476 to FD, so callers needn't bother with checking that the return
477 value equals to LEN. Instead, you should simply check for -1. */
480 iwrite (int fd, char *buf, int len)
484 /* `write' may write less than LEN bytes, thus the outward loop
485 keeps trying it until all was written, or an error occurred. The
486 inner loop is reserved for the usual EINTR f*kage, and the
487 innermost loop deals with the same during select(). */
491 if (opt.read_timeout)
492 if (select_fd (fd, opt.read_timeout, 1) <= 0)
496 res = WRITE (fd, buf, len);
497 while (res == -1 && errno == EINTR);