-/* Dealing with host names.
- Copyright (C) 1995, 1996, 1997, 2000 Free Software Foundation, Inc.
+/* Host name resolution and matching.
+ Copyright (C) 1995, 1996, 1997, 2000, 2001 Free Software Foundation, Inc.
This file is part of GNU Wget.
GNU Wget is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
-(at your option) any later version.
+ (at your option) any later version.
GNU Wget is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
You should have received a copy of the GNU General Public License
along with Wget; if not, write to the Free Software
-Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+In addition, as a special exception, the Free Software Foundation
+gives permission to link the code of its release of Wget with the
+OpenSSL project's "OpenSSL" library (or with modified versions of it
+that use the same license as the "OpenSSL" library), and distribute
+the linked executables. You must obey the GNU General Public License
+in all respects for all of the code used other than "OpenSSL". If you
+modify this file, you may extend this exception to your version of the
+file, but you are not obligated to do so. If you do not wish to do
+so, delete this exception statement from your version. */
#include <config.h>
+#ifndef WINDOWS
+#include <netdb.h>
+#endif
+
#include <stdio.h>
#include <stdlib.h>
#ifdef HAVE_STRING_H
#ifdef WINDOWS
# include <winsock.h>
+# define SET_H_ERRNO(err) WSASetLastError (err)
#else
# include <sys/socket.h>
# include <netinet/in.h>
-#ifndef __BEOS__
-# include <arpa/inet.h>
-#endif
+# ifndef __BEOS__
+# endif
# include <netdb.h>
+# define SET_H_ERRNO(err) ((void)(h_errno = (err)))
#endif /* WINDOWS */
#ifndef NO_ADDRESS
extern int errno;
#endif
-#define IP4_ADDRESS_LENGTH 4
+#ifndef h_errno
+# ifndef __CYGWIN__
+extern int h_errno;
+# endif
+#endif
+
+#ifdef ENABLE_IPV6
+int ip_default_family = AF_UNSPEC;
+#else
+int ip_default_family = AF_INET;
+#endif
/* Mapping between known hosts and to lists of their addresses. */
-struct hash_table *host_name_addresses_map;
+static struct hash_table *host_name_addresses_map;
\f
/* Lists of addresses. This should eventually be extended to handle
IPv6. */
struct address_list {
int count; /* number of adrresses */
- unsigned char *buffer; /* buffer which holds all of them. */
+ ip_address *addresses; /* pointer to the string of addresses */
- int faulty; /* number of addresses known not to
- work. */
- int refcount; /* so we know whether to free it or
- not. */
-};
+ int faulty; /* number of addresses known not to work. */
+ int from_cache; /* whether this entry was pulled from
+ cache or freshly looked up. */
-#define ADDR_LOCATION(al, index) ((al)->buffer + index * IP4_ADDRESS_LENGTH)
+ int refcount; /* reference count; when it drops to
+ 0, the entry is freed. */
+};
/* Get the bounds of the address list. */
void
-address_list_get_bounds (struct address_list *al, int *start, int *end)
+address_list_get_bounds (const struct address_list *al, int *start, int *end)
{
*start = al->faulty;
*end = al->count;
}
-/* Copy address number INDEX to IP_STORE. */
+/* Return whether this address list entry has been obtained from the
+ cache. */
-void
-address_list_copy_one (struct address_list *al, int index,
- unsigned char *ip_store)
+int
+address_list_cached_p (const struct address_list *al)
+{
+ return al->from_cache;
+}
+
+/* Return a pointer to the address at position POS. */
+
+const ip_address *
+address_list_address_at (const struct address_list *al, int pos)
{
- assert (index >= al->faulty && index < al->count);
- memcpy (ip_store, ADDR_LOCATION (al, index), IP4_ADDRESS_LENGTH);
+ assert (pos >= al->faulty && pos < al->count);
+ return al->addresses + pos;
}
/* Check whether two address lists have all their IPs in common. */
int
-address_list_match_all (struct address_list *al1, struct address_list *al2)
+address_list_match_all (const struct address_list *al1,
+ const struct address_list *al2)
{
+#ifdef ENABLE_IPV6
+ int i;
+#endif
if (al1 == al2)
return 1;
if (al1->count != al2->count)
return 0;
- return 0 == memcmp (al1->buffer, al2->buffer,
- al1->count * IP4_ADDRESS_LENGTH);
+
+ /* For the comparison to be complete, we'd need to sort the IP
+ addresses first. But that's not necessary because this is only
+ used as an optimization. */
+
+#ifndef ENABLE_IPV6
+ /* In the non-IPv6 case, there is only one address type, so we can
+ compare the whole array with memcmp. */
+ return 0 == memcmp (al1->addresses, al2->addresses,
+ al1->count * sizeof (ip_address));
+#else /* ENABLE_IPV6 */
+ for (i = 0; i < al1->count; ++i)
+ {
+ const ip_address *ip1 = &al1->addresses[i];
+ const ip_address *ip2 = &al2->addresses[i];
+
+ if (ip1->type != ip2->type)
+ return 0;
+
+ switch (ip1->type)
+ {
+ case IPV4_ADDRESS:
+ if (ADDRESS_IPV4_IN_ADDR (ip1).s_addr
+ != ADDRESS_IPV4_IN_ADDR (ip2).s_addr)
+ return 0;
+ break;
+ case IPV6_ADDRESS:
+#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
+ if (ADDRESS_IPV6_SCOPE (ip1) != ADDRESS_IPV6_SCOPE (ip2))
+ return 0;
+#endif /* HAVE_SOCKADDR_IN6_SCOPE_ID */
+ if (!IN6_ARE_ADDR_EQUAL (&ADDRESS_IPV6_IN6_ADDR (ip1),
+ &ADDRESS_IPV6_IN6_ADDR (ip2)))
+ return 0;
+ break;
+ default:
+ abort ();
+ }
+ }
+ return 1;
+#endif /* ENABLE_IPV6 */
}
/* Mark the INDEXth element of AL as faulty, so that the next time
void
address_list_set_faulty (struct address_list *al, int index)
{
+ /* We assume that the address list is traversed in order, so that a
+ "faulty" attempt is always preceded with all-faulty addresses,
+ and this is how Wget uses it. */
+ assert (index == al->faulty);
+
++al->faulty;
if (al->faulty >= al->count)
/* All addresses have been proven faulty. Since there's not much
al->faulty = 0;
}
-/* Create an address_list out of a NULL-terminated list of addresses,
- as returned by gethostbyname. */
-
+#ifdef ENABLE_IPV6
+/**
+ * address_list_from_addrinfo
+ *
+ * This function transform an addrinfo links list in and address_list.
+ *
+ * Input:
+ * addrinfo* Linked list of addrinfo
+ *
+ * Output:
+ * address_list* New allocated address_list
+ */
static struct address_list *
-address_list_new (char **h_addr_list)
+address_list_from_addrinfo (const struct addrinfo *ai)
{
- int count = 0, i;
+ struct address_list *al;
+ const struct addrinfo *ptr;
+ int cnt;
+ ip_address *ip;
+
+ cnt = 0;
+ for (ptr = ai; ptr != NULL ; ptr = ptr->ai_next)
+ if (ptr->ai_family == AF_INET || ptr->ai_family == AF_INET6)
+ ++cnt;
+ if (cnt == 0)
+ return NULL;
+
+ al = xnew0 (struct address_list);
+ al->addresses = xnew_array (ip_address, cnt);
+ al->count = cnt;
+ al->refcount = 1;
+
+ ip = al->addresses;
+ for (ptr = ai; ptr != NULL; ptr = ptr->ai_next)
+ if (ptr->ai_family == AF_INET6)
+ {
+ const struct sockaddr_in6 *sin6 =
+ (const struct sockaddr_in6 *)ptr->ai_addr;
+ ip->type = IPV6_ADDRESS;
+ ADDRESS_IPV6_IN6_ADDR (ip) = sin6->sin6_addr;
+#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
+ ADDRESS_IPV6_SCOPE (ip) = sin6->sin6_scope_id;
+#endif
+ ++ip;
+ }
+ else if (ptr->ai_family == AF_INET)
+ {
+ const struct sockaddr_in *sin =
+ (const struct sockaddr_in *)ptr->ai_addr;
+ ip->type = IPV4_ADDRESS;
+ ADDRESS_IPV4_IN_ADDR (ip) = sin->sin_addr;
+ ++ip;
+ }
+ assert (ip - al->addresses == cnt);
+ return al;
+}
+#else
+/* Create an address_list from a NULL-terminated vector of IPv4
+ addresses. This kind of vector is returned by gethostbyname. */
- struct address_list *al = xmalloc (sizeof (struct address_list));
+static struct address_list *
+address_list_from_ipv4_addresses (char **h_addr_list)
+{
+ int count, i;
+ struct address_list *al = xnew0 (struct address_list);
+ count = 0;
while (h_addr_list[count])
++count;
assert (count > 0);
- al->count = count;
- al->faulty = 0;
- al->buffer = xmalloc (count * IP4_ADDRESS_LENGTH);
- al->refcount = 1;
+
+ al->addresses = xnew_array (ip_address, count);
+ al->count = count;
+ al->refcount = 1;
for (i = 0; i < count; i++)
- memcpy (ADDR_LOCATION (al, i), h_addr_list[i], IP4_ADDRESS_LENGTH);
+ {
+ ip_address *ip = &al->addresses[i];
+ ip->type = IPV4_ADDRESS;
+ memcpy (ADDRESS_IPV4_DATA (ip), h_addr_list[i], 4);
+ }
return al;
}
+#endif
static void
address_list_delete (struct address_list *al)
{
- xfree (al->buffer);
+ xfree (al->addresses);
xfree (al);
}
}
}
\f
-/* The same as inet_ntoa, but without the need for a cast, or for
- #including the netinet stuff. */
+/* Versions of gethostbyname and getaddrinfo that support timeout. */
-char *
-pretty_print_address (const unsigned char *addr)
+#ifndef ENABLE_IPV6
+
+struct ghbnwt_context {
+ const char *host_name;
+ struct hostent *hptr;
+};
+
+static void
+gethostbyname_with_timeout_callback (void *arg)
+{
+ struct ghbnwt_context *ctx = (struct ghbnwt_context *)arg;
+ ctx->hptr = gethostbyname (ctx->host_name);
+}
+
+/* Just like gethostbyname, except it times out after TIMEOUT seconds.
+ In case of timeout, NULL is returned and errno is set to ETIMEDOUT.
+ The function makes sure that when NULL is returned for reasons
+ other than timeout, errno is reset. */
+
+static struct hostent *
+gethostbyname_with_timeout (const char *host_name, double timeout)
{
- return inet_ntoa (*(struct in_addr *)addr);
+ struct ghbnwt_context ctx;
+ ctx.host_name = host_name;
+ if (run_with_timeout (timeout, gethostbyname_with_timeout_callback, &ctx))
+ {
+ SET_H_ERRNO (HOST_NOT_FOUND);
+ errno = ETIMEDOUT;
+ return NULL;
+ }
+ if (!ctx.hptr)
+ errno = 0;
+ return ctx.hptr;
+}
+
+#else /* ENABLE_IPV6 */
+
+struct gaiwt_context {
+ const char *node;
+ const char *service;
+ const struct addrinfo *hints;
+ struct addrinfo **res;
+ int exit_code;
+};
+
+static void
+getaddrinfo_with_timeout_callback (void *arg)
+{
+ struct gaiwt_context *ctx = (struct gaiwt_context *)arg;
+ ctx->exit_code = getaddrinfo (ctx->node, ctx->service, ctx->hints, ctx->res);
+}
+
+/* Just like getaddrinfo, except it times out after TIMEOUT seconds.
+ In case of timeout, the EAI_SYSTEM error code is returned and errno
+ is set to ETIMEDOUT. */
+
+static int
+getaddrinfo_with_timeout (const char *node, const char *service,
+ const struct addrinfo *hints, struct addrinfo **res,
+ double timeout)
+{
+ struct gaiwt_context ctx;
+ ctx.node = node;
+ ctx.service = service;
+ ctx.hints = hints;
+ ctx.res = res;
+
+ if (run_with_timeout (timeout, getaddrinfo_with_timeout_callback, &ctx))
+ {
+ errno = ETIMEDOUT;
+ return EAI_SYSTEM;
+ }
+ return ctx.exit_code;
+}
+
+#endif /* ENABLE_IPV6 */
+\f
+/* Pretty-print ADDR. When compiled without IPv6, this is the same as
+ inet_ntoa. With IPv6, it either prints an IPv6 address or an IPv4
+ address. */
+
+const char *
+pretty_print_address (const ip_address *addr)
+{
+ switch (addr->type)
+ {
+ case IPV4_ADDRESS:
+ return inet_ntoa (ADDRESS_IPV4_IN_ADDR (addr));
+#ifdef ENABLE_IPV6
+ case IPV6_ADDRESS:
+ {
+ static char buf[128];
+ inet_ntop (AF_INET6, &ADDRESS_IPV6_IN6_ADDR (addr), buf, sizeof (buf));
+#if 0
+#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
+ {
+ /* append "%SCOPE_ID" for all ?non-global? addresses */
+ char *p = buf + strlen (buf);
+ *p++ = '%';
+ number_to_string (p, ADDRESS_IPV6_SCOPE (addr));
+ }
+#endif
+#endif
+ buf[sizeof (buf) - 1] = '\0';
+ return buf;
+ }
+#endif
+ }
+ abort ();
+ return NULL;
}
/* Add host name HOST with the address ADDR_TEXT to the cache.
++al->refcount;
hash_table_put (host_name_addresses_map, xstrdup_lower (host), al);
-#ifdef DEBUG
+#ifdef ENABLE_DEBUG
if (opt.debug)
{
int i;
debug_logprintf ("Caching %s =>", host);
for (i = 0; i < al->count; i++)
- debug_logprintf (" %s",
- pretty_print_address (ADDR_LOCATION (al, i)));
+ debug_logprintf (" %s", pretty_print_address (al->addresses + i));
debug_logprintf ("\n");
}
#endif
}
+void
+forget_host_lookup (const char *host)
+{
+ struct address_list *al = hash_table_get (host_name_addresses_map, host);
+ if (al)
+ {
+ address_list_release (al);
+ hash_table_remove (host_name_addresses_map, host);
+ }
+}
+
struct address_list *
-lookup_host (const char *host, int silent)
+lookup_host (const char *host, int flags)
{
struct address_list *al = NULL;
- unsigned long addr;
- struct hostent *hptr;
- /* If the address is of the form d.d.d.d, no further lookup is
- needed. */
- addr = (unsigned long)inet_addr (host);
- if ((int)addr != -1)
+#ifdef ENABLE_IPV6
+ int err, family;
+ struct addrinfo hints, *res;
+
+ /* Is this necessary? Should this function be changed to accept a
+ FAMILY argument? */
+ if (flags & LH_IPV4_ONLY)
+ family = AF_INET;
+ else if (flags & LH_IPV6_ONLY)
+ family = AF_INET6;
+ else
+ family = ip_default_family;
+#endif
+
+ /* First, try to check whether the address is already a numeric
+ address, in which case we don't need to cache it or bother with
+ setting up timeouts. Plus, if memory serves me right, Ultrix's
+ gethostbyname can't handle numeric addresses (!).
+
+ Where getaddrinfo is available, we do it using the AI_NUMERICHOST
+ flag. Without IPv6, we use inet_addr succeeds. */
+
+#ifdef ENABLE_IPV6
+ xzero (hints);
+ hints.ai_family = family;
+ hints.ai_socktype = SOCK_STREAM;
+ hints.ai_flags = AI_NUMERICHOST;
+ if (flags & LH_PASSIVE)
+ hints.ai_flags = AI_PASSIVE;
+
+ /* no need to call getaddrinfo_with_timeout here, as we're not
+ * relying on the DNS, but we're only doing an address translation
+ * from presentation (ASCII) to network format */
+ err = getaddrinfo (host, NULL, &hints, &res);
+ if (err == 0 && res != NULL)
{
- char tmpstore[IP4_ADDRESS_LENGTH];
- char *lst[] = { tmpstore, NULL };
-
- /* ADDR is defined to be in network byte order, which is what
- this returns, so we can just copy it to STORE_IP. However,
- on big endian 64-bit architectures the value will be stored
- in the *last*, not first four bytes. OFFSET makes sure that
- we copy the correct four bytes. */
- int offset;
-#ifdef WORDS_BIGENDIAN
- offset = sizeof (unsigned long) - IP4_ADDRESS_LENGTH;
+ al = address_list_from_addrinfo (res);
+ freeaddrinfo (res);
+ return al;
+ }
#else
- offset = 0;
+ {
+ uint32_t addr_ipv4 = (uint32_t)inet_addr (host);
+ if (addr_ipv4 != (uint32_t) -1)
+ {
+ /* The return value of inet_addr is in network byte order, so
+ we can just copy it to IP. */
+ char **vec[2];
+ vec[0] = (char *)&addr_ipv4;
+ vec[1] = NULL;
+ return address_list_from_ipv4_addresses (vec);
+ }
+ }
#endif
- memcpy (tmpstore, (char *)&addr + offset, IP4_ADDRESS_LENGTH);
- return address_list_new (lst);
- }
- /* By now we know that the host name we got is not of the form
- d.d.d.d. Try to find it in our cache of host names. */
- if (host_name_addresses_map)
- al = hash_table_get (host_name_addresses_map, host);
+ /* Then, try to find the host in the cache. */
- if (al)
+ if (host_name_addresses_map)
{
- DEBUGP (("Found %s in host_name_addresses_map (%p)\n", host, al));
- ++al->refcount;
- return al;
+ al = hash_table_get (host_name_addresses_map, host);
+ if (al)
+ {
+ DEBUGP (("Found %s in host_name_addresses_map (%p)\n", host, al));
+ ++al->refcount;
+ al->from_cache = 1;
+ return al;
+ }
}
- if (!silent)
+ if (!(flags & LH_SILENT))
logprintf (LOG_VERBOSE, _("Resolving %s... "), host);
- /* Look up the host using gethostbyname(). Note that we use
- gethostbyname() rather than ngethostbyname(), because we already
- know that the address is not numerical. */
- hptr = gethostbyname (host);
- if (!hptr)
+ /* Host name lookup goes on below. */
+
+#ifdef ENABLE_IPV6
+ {
+ xzero (hints);
+ hints.ai_family = family;
+ hints.ai_socktype = SOCK_STREAM;
+ if (flags & LH_PASSIVE)
+ hints.ai_flags = AI_PASSIVE;
+
+ err = getaddrinfo_with_timeout (host, NULL, &hints, &res, opt.dns_timeout);
+
+ if (err != 0 || res == NULL)
+ {
+ if (!(flags & LH_SILENT))
+ logprintf (LOG_VERBOSE, _("failed: %s.\n"),
+ err != EAI_SYSTEM ? gai_strerror (err) : strerror (errno));
+ return NULL;
+ }
+ al = address_list_from_addrinfo (res);
+ freeaddrinfo (res);
+ }
+#else
+ {
+ struct hostent *hptr = gethostbyname_with_timeout (host, opt.dns_timeout);
+ if (!hptr)
+ {
+ if (!(flags & LH_SILENT))
+ {
+ if (errno != ETIMEDOUT)
+ logprintf (LOG_VERBOSE, _("failed: %s.\n"), herrmsg (h_errno));
+ else
+ logputs (LOG_VERBOSE, _("failed: timed out.\n"));
+ }
+ return NULL;
+ }
+ assert (hptr->h_length == 4);
+ /* Do older systems have h_addr_list? */
+ al = address_list_from_ipv4_addresses (hptr->h_addr_list);
+ }
+#endif
+
+ /* Print the addresses determined by DNS lookup, but no more than
+ three. */
+ if (!(flags & LH_SILENT))
{
- if (!silent)
- logprintf (LOG_VERBOSE, _("failed: %s.\n"), herrmsg (h_errno));
- return NULL;
+ int i;
+ int printmax = al->count <= 3 ? al->count : 3;
+ for (i = 0; i < printmax; i++)
+ {
+ logprintf (LOG_VERBOSE, "%s",
+ pretty_print_address (al->addresses + i));
+ if (i < printmax - 1)
+ logputs (LOG_VERBOSE, ", ");
+ }
+ if (printmax != al->count)
+ logputs (LOG_VERBOSE, ", ...");
+ logputs (LOG_VERBOSE, "\n");
}
- if (!silent)
- logprintf (LOG_VERBOSE, _("done.\n"));
-
- al = address_list_new (hptr->h_addr_list);
-
/* Cache the lookup information. */
- cache_host_lookup (host, al);
+ if (opt.dns_cache)
+ cache_host_lookup (host, al);
return al;
}
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