/* Host name resolution and matching.
- Copyright (C) 1995, 1996, 1997, 2000, 2001 Free Software Foundation, Inc.
+ Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
+ 2004, 2005, 2006, 2007 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.
+the Free Software Foundation; either version 3 of the License, or
+ (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
GNU General Public License for more details.
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.
+along with Wget. If not, see <http://www.gnu.org/licenses/>.
In addition, as a special exception, the Free Software Foundation
gives permission to link the code of its release of Wget with 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 "wget.h"
#include <stdio.h>
#include <stdlib.h>
-#ifdef HAVE_STRING_H
-# include <string.h>
-#else
-# include <strings.h>
-#endif
+#include <string.h>
#include <assert.h>
-#include <sys/types.h>
-#ifdef WINDOWS
-# include <winsock.h>
-# define SET_H_ERRNO(err) WSASetLastError(err)
-#else
+#ifndef WINDOWS
# include <sys/socket.h>
# include <netinet/in.h>
# ifndef __BEOS__
# endif
# include <netdb.h>
# define SET_H_ERRNO(err) ((void)(h_errno = (err)))
+#else /* WINDOWS */
+# define SET_H_ERRNO(err) WSASetLastError (err)
#endif /* WINDOWS */
-#ifndef NO_ADDRESS
-#define NO_ADDRESS NO_DATA
-#endif
-
-#ifdef HAVE_SYS_UTSNAME_H
-# include <sys/utsname.h>
-#endif
#include <errno.h>
-#include "wget.h"
#include "utils.h"
#include "host.h"
#include "url.h"
#include "hash.h"
-#ifndef errno
-extern int errno;
-#endif
-
-#ifndef h_errno
-# ifndef __CYGWIN__
-extern int h_errno;
-# endif
-#endif
-
-#ifdef ENABLE_IPV6
-int ip_default_family = AF_INET6;
-#else
-int ip_default_family = AF_INET;
+#ifndef NO_ADDRESS
+# define NO_ADDRESS NO_DATA
#endif
-/* Mapping between known hosts and to lists of their addresses. */
-
-static struct hash_table *host_name_addresses_map;
-\f
-/* Lists of addresses. This should eventually be extended to handle
- IPv6. */
+/* Lists of IP addresses that result from running DNS queries. See
+ lookup_host for details. */
struct address_list {
- int count; /* number of adrresses */
- ip_address *addresses; /* pointer to the string of addresses */
+ int count; /* number of adrresses */
+ ip_address *addresses; /* pointer to the string of addresses */
+
+ int faulty; /* number of addresses known not to work. */
+ bool connected; /* whether we were able to connect to
+ one of the addresses in the list,
+ at least once. */
- int faulty; /* number of addresses known not to work. */
- int refcount; /* so we know whether to free it or not. */
+ 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 a pointer to the address at position POS. */
-void
-address_list_copy_one (struct address_list *al, int index, ip_address *ip_store)
+const ip_address *
+address_list_address_at (const struct address_list *al, int pos)
{
- assert (index >= al->faulty && index < al->count);
- memcpy (ip_store, al->addresses + index, sizeof (ip_address));
+ assert (pos >= al->faulty && pos < al->count);
+ return al->addresses + pos;
}
-/* Check whether two address lists have all their IPs in common. */
+/* Return true if AL contains IP, false otherwise. */
-int
-address_list_match_all (struct address_list *al1, struct address_list *al2)
+bool
+address_list_contains (const struct address_list *al, const ip_address *ip)
{
- if (al1 == al2)
- return 1;
- if (al1->count != al2->count)
- return 0;
- return 0 == memcmp (al1->addresses, al2->addresses,
- al1->count * sizeof (ip_address));
+ int i;
+ switch (ip->family)
+ {
+ case AF_INET:
+ for (i = 0; i < al->count; i++)
+ {
+ ip_address *cur = al->addresses + i;
+ if (cur->family == AF_INET
+ && (cur->data.d4.s_addr == ip->data.d4.s_addr))
+ return true;
+ }
+ return false;
+#ifdef ENABLE_IPV6
+ case AF_INET6:
+ for (i = 0; i < al->count; i++)
+ {
+ ip_address *cur = al->addresses + i;
+ if (cur->family == AF_INET6
+#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
+ && cur->ipv6_scope == ip->ipv6_scope
+#endif
+ && IN6_ARE_ADDR_EQUAL (&cur->data.d6, &ip->data.d6))
+ return true;
+ }
+ return false;
+#endif /* ENABLE_IPV6 */
+ default:
+ abort ();
+ }
}
/* Mark the INDEXth element of AL as faulty, so that the next time
al->faulty = 0;
}
-#ifdef HAVE_GETADDRINFO
-/**
- * address_list_from_addrinfo
- *
- * This function transform an addrinfo links list in and address_list.
- *
- * Input:
- * addrinfo* Linkt list of addrinfo
- *
- * Output:
- * address_list* New allocated address_list
- */
+/* Set the "connected" flag to true. This flag used by connect.c to
+ see if the host perhaps needs to be resolved again. */
+
+void
+address_list_set_connected (struct address_list *al)
+{
+ al->connected = true;
+}
+
+/* Return the value of the "connected" flag. */
+
+bool
+address_list_connected_p (const struct address_list *al)
+{
+ return al->connected;
+}
+
+#ifdef ENABLE_IPV6
+
+/* Create an address_list from the addresses in the given struct
+ addrinfo. */
+
static struct address_list *
-address_list_from_addrinfo (struct addrinfo *ai)
+address_list_from_addrinfo (const struct addrinfo *ai)
{
struct address_list *al;
- struct addrinfo *ai_head = ai;
- int cnt = 0;
- int i;
+ const struct addrinfo *ptr;
+ int cnt;
+ ip_address *ip;
- for (ai = ai_head; ai; ai = ai->ai_next)
- if (ai->ai_family == AF_INET || ai->ai_family == AF_INET6)
+ 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 = xmalloc (sizeof (struct address_list));
- al->addresses = xmalloc (cnt * sizeof (ip_address));
+ al = xnew0 (struct address_list);
+ al->addresses = xnew_array (ip_address, cnt);
al->count = cnt;
- al->faulty = 0;
al->refcount = 1;
- for (i = 0, ai = ai_head; ai; ai = ai->ai_next)
- if (ai->ai_family == AF_INET6)
+ ip = al->addresses;
+ for (ptr = ai; ptr != NULL; ptr = ptr->ai_next)
+ if (ptr->ai_family == AF_INET6)
{
- struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)ai->ai_addr;
- memcpy (al->addresses + i, &sin6->sin6_addr, 16);
- ++i;
+ const struct sockaddr_in6 *sin6 =
+ (const struct sockaddr_in6 *)ptr->ai_addr;
+ ip->family = AF_INET6;
+ ip->data.d6 = sin6->sin6_addr;
+#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
+ ip->ipv6_scope = sin6->sin6_scope_id;
+#endif
+ ++ip;
}
- else if (ai->ai_family == AF_INET)
+ else if (ptr->ai_family == AF_INET)
{
- struct sockaddr_in *sin = (struct sockaddr_in *)ai->ai_addr;
- map_ipv4_to_ip ((ip4_address *)&sin->sin_addr, al->addresses + i);
- ++i;
+ const struct sockaddr_in *sin =
+ (const struct sockaddr_in *)ptr->ai_addr;
+ ip->family = AF_INET;
+ ip->data.d4 = sin->sin_addr;
+ ++ip;
}
- assert (i == cnt);
+ assert (ip - al->addresses == cnt);
return al;
}
-#else
-/* Create an address_list out of a NULL-terminated list of addresses,
- as returned by gethostbyname. */
-static struct address_list *
-address_list_new (char **h_addr_list)
-{
- int count = 0, i;
- struct address_list *al = xmalloc (sizeof (struct address_list));
+#define IS_IPV4(addr) (((const ip_address *) addr)->family == AF_INET)
- while (h_addr_list[count])
- ++count;
- assert (count > 0);
- al->count = count;
- al->faulty = 0;
- al->addresses = xmalloc (count * sizeof (ip_address));
- al->refcount = 1;
+/* Compare two IP addresses by family, giving preference to the IPv4
+ address (sorting it first). In other words, return -1 if ADDR1 is
+ IPv4 and ADDR2 is IPv6, +1 if ADDR1 is IPv6 and ADDR2 is IPv4, and
+ 0 otherwise.
- for (i = 0; i < count; i++)
- map_ipv4_to_ip ((ip4_address *)h_addr_list[i], al->addresses + i);
+ This is intended to be used as the comparator arg to a qsort-like
+ sorting function, which is why it accepts generic pointers. */
- return al;
+static int
+cmp_prefer_ipv4 (const void *addr1, const void *addr2)
+{
+ return !IS_IPV4 (addr1) - !IS_IPV4 (addr2);
}
-#endif
-/* Like address_list_new, but initialized with only one address. */
+#define IS_IPV6(addr) (((const ip_address *) addr)->family == AF_INET6)
+
+/* Like the above, but give preference to the IPv6 address. */
+
+static int
+cmp_prefer_ipv6 (const void *addr1, const void *addr2)
+{
+ return !IS_IPV6 (addr1) - !IS_IPV6 (addr2);
+}
+
+#else /* not ENABLE_IPV6 */
+
+/* Create an address_list from a NULL-terminated vector of IPv4
+ addresses. This kind of vector is returned by gethostbyname. */
static struct address_list *
-address_list_new_one (ip_address *addr)
+address_list_from_ipv4_addresses (char **vec)
{
- struct address_list *al = xmalloc (sizeof (struct address_list));
- al->count = 1;
- al->faulty = 0;
- al->addresses = xmalloc (sizeof (ip_address));
+ int count, i;
+ struct address_list *al = xnew0 (struct address_list);
+
+ count = 0;
+ while (vec[count])
+ ++count;
+ assert (count > 0);
+
+ al->addresses = xnew_array (ip_address, count);
+ al->count = count;
al->refcount = 1;
- memcpy (al->addresses, addr, sizeof (ip_address));
+
+ for (i = 0; i < count; i++)
+ {
+ ip_address *ip = &al->addresses[i];
+ ip->family = AF_INET;
+ memcpy (IP_INADDR_DATA (ip), vec[i], 4);
+ }
return al;
}
+#endif /* not ENABLE_IPV6 */
+
static void
address_list_delete (struct address_list *al)
{
xfree (al);
}
+/* Mark the address list as being no longer in use. This will reduce
+ its reference count which will cause the list to be freed when the
+ count reaches 0. */
+
void
address_list_release (struct address_list *al)
{
--al->refcount;
- DEBUGP (("Releasing %p (new refcount %d).\n", al, al->refcount));
+ DEBUGP (("Releasing 0x%0*lx (new refcount %d).\n", PTR_FORMAT (al),
+ al->refcount));
if (al->refcount <= 0)
{
- DEBUGP (("Deleting unused %p.\n", al));
+ DEBUGP (("Deleting unused 0x%0*lx.\n", PTR_FORMAT (al)));
address_list_delete (al);
}
}
\f
-/**
- * wget_sockaddr_set_address
- *
- * This function takes an wget_sockaddr and fill in the protocol type,
- * the port number and the address, there NULL in address means wildcard.
- * Unsuported adress family will abort the whole programm.
- *
- * Input:
- * wget_sockaddr* The space to be filled
- * int The wished protocol
- * unsigned short The port
- * const ip_address The Binary IP adress
- *
- * Return:
- * - Only modify 1. param
- */
-void
-wget_sockaddr_set_address (wget_sockaddr *sa,
- int ip_family, unsigned short port, ip_address *addr)
-{
- if (ip_family == AF_INET)
- {
- sa->sin.sin_family = ip_family;
- sa->sin.sin_port = htons (port);
- if (addr == NULL)
- memset (&sa->sin.sin_addr, 0, sizeof(ip4_address));
- else
- {
- ip4_address addr4;
- if (!map_ip_to_ipv4 (addr, &addr4))
- /* should the callers have prevented this? */
- abort ();
- memcpy (&sa->sin.sin_addr, &addr4, sizeof(ip4_address));
- }
- return;
- }
-#ifdef ENABLE_IPV6
- if (ip_family == AF_INET6)
- {
- sa->sin6.sin6_family = ip_family;
- sa->sin6.sin6_port = htons (port);
- if (addr == NULL)
- memset (&sa->sin6.sin6_addr, 0 , 16);
- else
- memcpy (&sa->sin6.sin6_addr, addr, 16);
- return;
- }
-#endif
- abort();
-}
-
-/**
- * wget_sockaddr_set_port
- *
- * This funtion only fill the port of the socket information.
- * If the protocol is not supported nothing is done.
- * Unsuported adress family will abort the whole programm.
- *
- * Require:
- * that the IP-Protocol already is set.
- *
- * Input:
- * wget_sockaddr* The space there port should be entered
- * unsigned int The port that should be entered in host order
- *
- * Return:
- * - Only modify 1. param
- */
-void
-wget_sockaddr_set_port (wget_sockaddr *sa, unsigned short port)
-{
- if (sa->sa.sa_family == AF_INET)
- {
- sa->sin.sin_port = htons (port);
- return;
- }
-#ifdef ENABLE_IPV6
- if (sa->sa.sa_family == AF_INET6)
- {
- sa->sin6.sin6_port = htons (port);
- return;
- }
-#endif
- abort();
-}
-
-/**
- * wget_sockaddr_get_addr
- *
- * This function return the adress from an sockaddr as byte string.
- * Unsuported adress family will abort the whole programm.
- *
- * Require:
- * that the IP-Protocol already is set.
- *
- * Input:
- * wget_sockaddr* Socket Information
- *
- * Output:
- * unsigned char * IP address as byte string.
- */
-void *
-wget_sockaddr_get_addr (wget_sockaddr *sa)
-{
- if (sa->sa.sa_family == AF_INET)
- return &sa->sin.sin_addr;
-#ifdef ENABLE_IPV6
- if (sa->sa.sa_family == AF_INET6)
- return &sa->sin6.sin6_addr;
-#endif
- abort();
- /* unreached */
- return NULL;
-}
-
-/**
- * wget_sockaddr_get_port
- *
- * This function only return the port from the input structure
- * Unsuported adress family will abort the whole programm.
- *
- * Require:
- * that the IP-Protocol already is set.
- *
- * Input:
- * wget_sockaddr* Information where to get the port
- *
- * Output:
- * unsigned short Port Number in host order.
- */
-unsigned short
-wget_sockaddr_get_port (const wget_sockaddr *sa)
-{
- if (sa->sa.sa_family == AF_INET)
- return htons (sa->sin.sin_port);
-#ifdef ENABLE_IPV6
- if (sa->sa.sa_family == AF_INET6)
- return htons (sa->sin6.sin6_port);
-#endif
- abort();
- /* do not complain about return nothing */
- return -1;
-}
-
-/**
- * sockaddr_len
- *
- * This function return the length of the sockaddr corresponding to
- * the acutall prefered protocol for (bind, connect etc...)
- * Unsuported adress family will abort the whole programm.
- *
- * Require:
- * that the IP-Protocol already is set.
- *
- * Input:
- * - Public IP-Family Information
- *
- * Output:
- * int structure length for socket options
- */
-int
-sockaddr_len ()
-{
- if (ip_default_family == AF_INET)
- return sizeof (struct sockaddr_in);
-#ifdef ENABLE_IPV6
- if (ip_default_family == AF_INET6)
- return sizeof (struct sockaddr_in6);
-#endif
- abort();
- /* do not complain about return nothing */
- return 0;
-}
-
-/**
- * Map an IPv4 adress to the internal adress format.
- */
-void
-map_ipv4_to_ip (ip4_address *ipv4, ip_address *ip)
-{
-#ifdef ENABLE_IPV6
- static unsigned char ipv64[12] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff};
- memcpy ((char *)ip + 12, ipv4 , 4);
- memcpy ((char *)ip + 0, ipv64, 12);
-#else
- if ((char *)ip != (char *)ipv4)
- memcpy (ip, ipv4, 4);
-#endif
-}
-
-/* Detect whether an IP adress represents an IPv4 address and, if so,
- copy it to IPV4. 0 is returned on failure.
- This operation always succeeds when Wget is compiled without IPv6.
- If IPV4 is NULL, don't copy, just detect. */
-
-int
-map_ip_to_ipv4 (ip_address *ip, ip4_address *ipv4)
-{
-#ifdef ENABLE_IPV6
- static unsigned char ipv64[12] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff};
- if (0 != memcmp (ip, ipv64, 12))
- return 0;
- if (ipv4)
- memcpy (ipv4, (char *)ip + 12, 4);
-#else
- if (ipv4)
- memcpy (ipv4, (char *)ip, 4);
-#endif
- return 1;
-}
-\f
/* Versions of gethostbyname and getaddrinfo that support timeout. */
#ifndef ENABLE_IPV6
other than timeout, errno is reset. */
static struct hostent *
-gethostbyname_with_timeout (const char *host_name, int timeout)
+gethostbyname_with_timeout (const char *host_name, double timeout)
{
struct ghbnwt_context ctx;
ctx.host_name = host_name;
return ctx.hptr;
}
+/* Print error messages for host errors. */
+static char *
+host_errstr (int error)
+{
+ /* Can't use switch since some of these constants can be equal,
+ which makes the compiler complain about duplicate case
+ values. */
+ if (error == HOST_NOT_FOUND
+ || error == NO_RECOVERY
+ || error == NO_DATA
+ || error == NO_ADDRESS)
+ return _("Unknown host");
+ else if (error == TRY_AGAIN)
+ /* Message modeled after what gai_strerror returns in similar
+ circumstances. */
+ return _("Temporary failure in name resolution");
+ else
+ return _("Unknown error");
+}
+
#else /* ENABLE_IPV6 */
struct gaiwt_context {
static int
getaddrinfo_with_timeout (const char *node, const char *service,
- const struct addrinfo *hints, struct addrinfo **res,
- int timeout)
+ const struct addrinfo *hints, struct addrinfo **res,
+ double timeout)
{
struct gaiwt_context ctx;
ctx.node = node;
#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. */
+/* Return a textual representation of ADDR, i.e. the dotted quad for
+ IPv4 addresses, and the colon-separated list of hex words (with all
+ zeros omitted, etc.) for IPv6 addresses. */
-char *
-pretty_print_address (ip_address *addr)
+const char *
+print_address (const ip_address *addr)
{
#ifdef ENABLE_IPV6
- ip4_address addr4;
- static char buf[128];
-
- if (map_ip_to_ipv4 (addr, &addr4))
- return inet_ntoa (*(struct in_addr *)&addr4);
-
- if (!inet_ntop (AF_INET6, addr, buf, sizeof (buf)))
- return "<unknown>";
+ static char buf[64];
+ if (!inet_ntop (addr->family, IP_INADDR_DATA (addr), buf, sizeof buf))
+ snprintf (buf, sizeof buf, "<error: %s>", strerror (errno));
return buf;
+#else
+ return inet_ntoa (addr->data.d4);
#endif
- return inet_ntoa (*(struct in_addr *)addr);
}
-/* Add host name HOST with the address ADDR_TEXT to the cache.
- ADDR_LIST is a NULL-terminated list of addresses, as in struct
- hostent. */
+/* The following two functions were adapted from glibc's
+ implementation of inet_pton, written by Paul Vixie. */
+
+static bool
+is_valid_ipv4_address (const char *str, const char *end)
+{
+ bool saw_digit = false;
+ int octets = 0;
+ int val = 0;
+
+ while (str < end)
+ {
+ int ch = *str++;
+
+ if (ch >= '0' && ch <= '9')
+ {
+ val = val * 10 + (ch - '0');
+
+ if (val > 255)
+ return false;
+ if (!saw_digit)
+ {
+ if (++octets > 4)
+ return false;
+ saw_digit = true;
+ }
+ }
+ else if (ch == '.' && saw_digit)
+ {
+ if (octets == 4)
+ return false;
+ val = 0;
+ saw_digit = false;
+ }
+ else
+ return false;
+ }
+ if (octets < 4)
+ return false;
+
+ return true;
+}
+
+bool
+is_valid_ipv6_address (const char *str, const char *end)
+{
+ /* Use lower-case for these to avoid clash with system headers. */
+ enum {
+ ns_inaddrsz = 4,
+ ns_in6addrsz = 16,
+ ns_int16sz = 2
+ };
+
+ const char *curtok;
+ int tp;
+ const char *colonp;
+ bool saw_xdigit;
+ unsigned int val;
+
+ tp = 0;
+ colonp = NULL;
+
+ if (str == end)
+ return false;
+
+ /* Leading :: requires some special handling. */
+ if (*str == ':')
+ {
+ ++str;
+ if (str == end || *str != ':')
+ return false;
+ }
+
+ curtok = str;
+ saw_xdigit = false;
+ val = 0;
+
+ while (str < end)
+ {
+ int ch = *str++;
+
+ /* if ch is a number, add it to val. */
+ if (c_isxdigit (ch))
+ {
+ val <<= 4;
+ val |= XDIGIT_TO_NUM (ch);
+ if (val > 0xffff)
+ return false;
+ saw_xdigit = true;
+ continue;
+ }
+
+ /* if ch is a colon ... */
+ if (ch == ':')
+ {
+ curtok = str;
+ if (!saw_xdigit)
+ {
+ if (colonp != NULL)
+ return false;
+ colonp = str + tp;
+ continue;
+ }
+ else if (str == end)
+ return false;
+ if (tp > ns_in6addrsz - ns_int16sz)
+ return false;
+ tp += ns_int16sz;
+ saw_xdigit = false;
+ val = 0;
+ continue;
+ }
+
+ /* if ch is a dot ... */
+ if (ch == '.' && (tp <= ns_in6addrsz - ns_inaddrsz)
+ && is_valid_ipv4_address (curtok, end) == 1)
+ {
+ tp += ns_inaddrsz;
+ saw_xdigit = false;
+ break;
+ }
+
+ return false;
+ }
+
+ if (saw_xdigit)
+ {
+ if (tp > ns_in6addrsz - ns_int16sz)
+ return false;
+ tp += ns_int16sz;
+ }
+
+ if (colonp != NULL)
+ {
+ if (tp == ns_in6addrsz)
+ return false;
+ tp = ns_in6addrsz;
+ }
+
+ if (tp != ns_in6addrsz)
+ return false;
+
+ return true;
+}
+\f
+/* Simple host cache, used by lookup_host to speed up resolving. The
+ cache doesn't handle TTL because Wget is a fairly short-lived
+ application. Refreshing is attempted when connect fails, though --
+ see connect_to_host. */
+
+/* Mapping between known hosts and to lists of their addresses. */
+static struct hash_table *host_name_addresses_map;
+
+
+/* Return the host's resolved addresses from the cache, if
+ available. */
+
+static struct address_list *
+cache_query (const char *host)
+{
+ struct address_list *al;
+ if (!host_name_addresses_map)
+ return NULL;
+ 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;
+ return al;
+ }
+ return NULL;
+}
+
+/* Cache the DNS lookup of HOST. Subsequent invocations of
+ lookup_host will return the cached value. */
static void
-cache_host_lookup (const char *host, struct address_list *al)
+cache_store (const char *host, struct address_list *al)
{
if (!host_name_addresses_map)
host_name_addresses_map = make_nocase_string_hash_table (0);
++al->refcount;
hash_table_put (host_name_addresses_map, xstrdup_lower (host), al);
-#ifdef DEBUG
- if (opt.debug)
+ IF_DEBUG
{
int i;
debug_logprintf ("Caching %s =>", host);
for (i = 0; i < al->count; i++)
- debug_logprintf (" %s", pretty_print_address (al->addresses + i));
+ debug_logprintf (" %s", print_address (al->addresses + i));
debug_logprintf ("\n");
}
-#endif
}
-struct address_list *
-lookup_host (const char *host, int silent)
+/* Remove HOST from the DNS cache. Does nothing is HOST is not in
+ the cache. */
+
+static void
+cache_remove (const char *host)
{
- struct address_list *al = NULL;
- unsigned long addr_ipv4; /* #### use a 32-bit type here. */
- ip_address addr;
+ struct address_list *al;
+ if (!host_name_addresses_map)
+ return;
+ al = hash_table_get (host_name_addresses_map, host);
+ if (al)
+ {
+ address_list_release (al);
+ hash_table_remove (host_name_addresses_map, host);
+ }
+}
+\f
+/* Look up HOST in DNS and return a list of IP addresses.
+
+ This function caches its result so that, if the same host is passed
+ the second time, the addresses are returned without DNS lookup.
+ (Use LH_REFRESH to force lookup, or set opt.dns_cache to 0 to
+ globally disable caching.)
+
+ The order of the returned addresses is affected by the setting of
+ opt.prefer_family: if it is set to prefer_ipv4, IPv4 addresses are
+ placed at the beginning; if it is prefer_ipv6, IPv6 ones are placed
+ at the beginning; otherwise, the order is left intact. The
+ relative order of addresses with the same family is left
+ undisturbed in either case.
+
+ FLAGS can be a combination of:
+ LH_SILENT - don't print the "resolving ... done" messages.
+ LH_BIND - resolve addresses for use with bind, which under
+ IPv6 means to use AI_PASSIVE flag to getaddrinfo.
+ Passive lookups are not cached under IPv6.
+ LH_REFRESH - if HOST is cached, remove the entry from the cache
+ and resolve it anew. */
- /* First, try to check whether the address is already a numeric
- address. */
+struct address_list *
+lookup_host (const char *host, int flags)
+{
+ struct address_list *al;
+ bool silent = !!(flags & LH_SILENT);
+ bool use_cache;
+ bool numeric_address = false;
+ double timeout = opt.dns_timeout;
-#ifdef ENABLE_IPV6
- if (inet_pton (AF_INET6, host, &addr) > 0)
- return address_list_new_one (&addr);
+#ifndef ENABLE_IPV6
+ /* If we're not using getaddrinfo, first check if HOST specifies a
+ numeric IPv4 address. Some implementations of gethostbyname
+ (e.g. the Ultrix one and possibly Winsock) don't accept
+ dotted-decimal IPv4 addresses. */
+ {
+ uint32_t addr_ipv4 = (uint32_t)inet_addr (host);
+ if (addr_ipv4 != (uint32_t) -1)
+ {
+ /* No need to cache host->addr relation, just return the
+ address. */
+ char *vec[2];
+ vec[0] = (char *)&addr_ipv4;
+ vec[1] = NULL;
+ return address_list_from_ipv4_addresses (vec);
+ }
+ }
+#else /* ENABLE_IPV6 */
+ /* If we're using getaddrinfo, at least check whether the address is
+ already numeric, in which case there is no need to print the
+ "Resolving..." output. (This comes at no additional cost since
+ the is_valid_ipv*_address are already required for
+ url_parse.) */
+ {
+ const char *end = host + strlen (host);
+ if (is_valid_ipv4_address (host, end) || is_valid_ipv6_address (host, end))
+ numeric_address = true;
+ }
#endif
- addr_ipv4 = (unsigned long)inet_addr (host);
- if ((int)addr_ipv4 != -1)
- {
- /* 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 = 0;
-#ifdef WORDS_BIGENDIAN
- offset = sizeof (unsigned long) - sizeof (ip4_address);
+ /* Cache is normally on, but can be turned off with --no-dns-cache.
+ Don't cache passive lookups under IPv6. */
+ use_cache = opt.dns_cache;
+#ifdef ENABLE_IPV6
+ if ((flags & LH_BIND) || numeric_address)
+ use_cache = false;
#endif
- map_ipv4_to_ip ((ip4_address *)((char *)&addr_ipv4 + offset), &addr);
- return address_list_new_one (&addr);
- }
- if (host_name_addresses_map)
+ /* Try to find the host in the cache so we don't need to talk to the
+ resolver. If LH_REFRESH is requested, remove HOST from the cache
+ instead. */
+ if (use_cache)
{
- 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;
- return al;
- }
+ if (!(flags & LH_REFRESH))
+ {
+ al = cache_query (host);
+ if (al)
+ return al;
+ }
+ else
+ cache_remove (host);
}
- if (!silent)
- logprintf (LOG_VERBOSE, _("Resolving %s... "), host);
+ /* No luck with the cache; resolve HOST. */
- /* Host name lookup goes on below. */
+ if (!silent && !numeric_address)
+ logprintf (LOG_VERBOSE, _("Resolving %s... "), escnonprint (host));
-#ifdef HAVE_GETADDRINFO
+#ifdef ENABLE_IPV6
{
- struct addrinfo hints, *ai;
int err;
+ struct addrinfo hints, *res;
- memset (&hints, 0, sizeof (hints));
- if (ip_default_family == AF_INET)
- hints.ai_family = AF_INET;
- else
- hints.ai_family = PF_UNSPEC;
+ xzero (hints);
hints.ai_socktype = SOCK_STREAM;
- err = getaddrinfo_with_timeout (host, NULL, &hints, &ai, opt.timeout);
+ if (opt.ipv4_only)
+ hints.ai_family = AF_INET;
+ else if (opt.ipv6_only)
+ hints.ai_family = AF_INET6;
+ else
+ /* We tried using AI_ADDRCONFIG, but removed it because: it
+ misinterprets IPv6 loopbacks, it is broken on AIX 5.1, and
+ it's unneeded since we sort the addresses anyway. */
+ hints.ai_family = AF_UNSPEC;
+
+ if (flags & LH_BIND)
+ hints.ai_flags |= AI_PASSIVE;
+
+#ifdef AI_NUMERICHOST
+ if (numeric_address)
+ {
+ /* Where available, the AI_NUMERICHOST hint can prevent costly
+ access to DNS servers. */
+ hints.ai_flags |= AI_NUMERICHOST;
+ timeout = 0; /* no timeout needed when "resolving"
+ numeric hosts -- avoid setting up
+ signal handlers and such. */
+ }
+#endif
- if (err != 0 || ai == NULL)
+ err = getaddrinfo_with_timeout (host, NULL, &hints, &res, timeout);
+ if (err != 0 || res == NULL)
{
if (!silent)
- logprintf (LOG_VERBOSE, _("failed: %s.\n"),
- err != EAI_SYSTEM ? gai_strerror (err) : strerror (errno));
+ logprintf (LOG_VERBOSE, _("failed: %s.\n"),
+ err != EAI_SYSTEM ? gai_strerror (err) : strerror (errno));
+ return NULL;
+ }
+ al = address_list_from_addrinfo (res);
+ freeaddrinfo (res);
+ if (!al)
+ {
+ logprintf (LOG_VERBOSE,
+ _("failed: No IPv4/IPv6 addresses for host.\n"));
return NULL;
}
- al = address_list_from_addrinfo (ai);
- freeaddrinfo (ai);
+
+ /* Reorder addresses so that IPv4 ones (or IPv6 ones, as per
+ --prefer-family) come first. Sorting is stable so the order of
+ the addresses with the same family is undisturbed. */
+ if (al->count > 1 && opt.prefer_family != prefer_none)
+ stable_sort (al->addresses, al->count, sizeof (ip_address),
+ opt.prefer_family == prefer_ipv4
+ ? cmp_prefer_ipv4 : cmp_prefer_ipv6);
}
-#else
+#else /* not ENABLE_IPV6 */
{
- struct hostent *hptr = gethostbyname_with_timeout (host, opt.timeout);
+ struct hostent *hptr = gethostbyname_with_timeout (host, timeout);
if (!hptr)
{
- if (!silent)
- {
- if (errno != ETIMEDOUT)
- logprintf (LOG_VERBOSE, _("failed: %s.\n"), herrmsg (h_errno));
- else
- logputs (LOG_VERBOSE, _("failed: timed out.\n"));
- }
- return NULL;
+ if (!silent)
+ {
+ if (errno != ETIMEDOUT)
+ logprintf (LOG_VERBOSE, _("failed: %s.\n"),
+ host_errstr (h_errno));
+ else
+ logputs (LOG_VERBOSE, _("failed: timed out.\n"));
+ }
+ return NULL;
}
- /* Do all systems have h_addr_list, or is it a newer thing? If
- the latter, use address_list_new_one. */
- al = address_list_new (hptr->h_addr_list);
+ /* Do older systems have h_addr_list? */
+ al = address_list_from_ipv4_addresses (hptr->h_addr_list);
}
-#endif
+#endif /* not ENABLE_IPV6 */
- if (!silent)
- logprintf (LOG_VERBOSE, _("done.\n"));
+ /* Print the addresses determined by DNS lookup, but no more than
+ three. */
+ if (!silent && !numeric_address)
+ {
+ int i;
+ int printmax = al->count <= 3 ? al->count : 3;
+ for (i = 0; i < printmax; i++)
+ {
+ logputs (LOG_VERBOSE, print_address (al->addresses + i));
+ if (i < printmax - 1)
+ logputs (LOG_VERBOSE, ", ");
+ }
+ if (printmax != al->count)
+ logputs (LOG_VERBOSE, ", ...");
+ logputs (LOG_VERBOSE, "\n");
+ }
/* Cache the lookup information. */
- cache_host_lookup (host, al);
+ if (use_cache)
+ cache_store (host, al);
return al;
}
\f
/* Determine whether a URL is acceptable to be followed, according to
a list of domains to accept. */
-int
+bool
accept_domain (struct url *u)
{
assert (u->host != NULL);
if (opt.domains)
{
if (!sufmatch ((const char **)opt.domains, u->host))
- return 0;
+ return false;
}
if (opt.exclude_domains)
{
if (sufmatch ((const char **)opt.exclude_domains, u->host))
- return 0;
+ return false;
}
- return 1;
+ return true;
}
/* Check whether WHAT is matched in LIST, each element of LIST being a
match_backwards() in utils.c).
If an element of LIST matched, 1 is returned, 0 otherwise. */
-int
+bool
sufmatch (const char **list, const char *what)
{
int i, j, k, lw;
for (i = 0; list[i]; i++)
{
for (j = strlen (list[i]), k = lw; j >= 0 && k >= 0; j--, k--)
- if (TOLOWER (list[i][j]) != TOLOWER (what[k]))
- break;
+ if (c_tolower (list[i][j]) != c_tolower (what[k]))
+ break;
/* The domain must be first to reach to beginning. */
if (j == -1)
- return 1;
+ return true;
}
- return 0;
-}
-
-/* Print error messages for host errors. */
-char *
-herrmsg (int error)
-{
- /* Can't use switch since some constants are equal (at least on my
- system), and the compiler signals "duplicate case value". */
- if (error == HOST_NOT_FOUND
- || error == NO_RECOVERY
- || error == NO_DATA
- || error == NO_ADDRESS
- || error == TRY_AGAIN)
- return _("Host not found");
- else
- return _("Unknown error");
-}
-
-static int
-host_cleanup_mapper (void *key, void *value, void *arg_ignored)
-{
- struct address_list *al;
-
- xfree (key); /* host */
-
- al = (struct address_list *)value;
- assert (al->refcount == 1);
- address_list_delete (al);
-
- return 0;
+ return false;
}
void
{
if (host_name_addresses_map)
{
- hash_table_map (host_name_addresses_map, host_cleanup_mapper, NULL);
+ hash_table_iterator iter;
+ for (hash_table_iterate (host_name_addresses_map, &iter);
+ hash_table_iter_next (&iter);
+ )
+ {
+ char *host = iter.key;
+ struct address_list *al = iter.value;
+ xfree (host);
+ assert (al->refcount == 1);
+ address_list_delete (al);
+ }
hash_table_destroy (host_name_addresses_map);
host_name_addresses_map = NULL;
}
projects / wget / blobdiff