-/* Dealing with host names.
- Copyright (C) 1995, 1996, 1997 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 Wget.
+This file is part of GNU Wget.
-This program is free software; you can redistribute it and/or modify
+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.
-This program is distributed in the hope that it will be useful,
+GNU Wget is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
+along with Wget; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
-#include <ctype.h>
#ifdef HAVE_STRING_H
# include <string.h>
#else
#else
# include <sys/socket.h>
# include <netinet/in.h>
-# include <arpa/inet.h>
+# ifndef __BEOS__
+# include <arpa/inet.h>
+# endif
# include <netdb.h>
#endif /* WINDOWS */
+#ifndef NO_ADDRESS
+#define NO_ADDRESS NO_DATA
+#endif
+
#ifdef HAVE_SYS_UTSNAME_H
# include <sys/utsname.h>
#endif
#include "utils.h"
#include "host.h"
#include "url.h"
+#include "hash.h"
#ifndef errno
extern int errno;
#endif
-/* Host list entry */
-struct host
-{
- /* Host's symbolical name, as encountered at the time of first
- inclusion, e.g. "fly.cc.fer.hr". */
- char *hostname;
- /* Host's "real" name, i.e. its IP address, written out in ASCII
- form of N.N.N.N, e.g. "161.53.70.130". */
- char *realname;
- /* More than one HOSTNAME can correspond to the same REALNAME. For
- our purposes, the canonical name of the host is its HOSTNAME when
- it was first encountered. This entry is said to have QUALITY. */
- int quality;
- /* Next entry in the list. */
- struct host *next;
+#ifndef h_errno
+# ifndef __CYGWIN__
+extern int h_errno;
+# endif
+#endif
+
+#define IP4_ADDRESS_LENGTH 4
+
+/* 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. */
+
+struct address_list {
+ int count; /* number of adrresses */
+ unsigned char *buffer; /* buffer which holds all of them. */
+
+ int faulty; /* number of addresses known not to
+ work. */
+ int refcount; /* so we know whether to free it or
+ not. */
};
-static struct host *hlist;
+#define ADDR_LOCATION(al, index) ((al)->buffer + index * IP4_ADDRESS_LENGTH)
-static struct host *add_hlist PARAMS ((struct host *, const char *,
- const char *, int));
+/* Get the bounds of the address list. */
-/* The same as gethostbyname, but supports internet addresses of the
- form `N.N.N.N'. */
-struct hostent *
-ngethostbyname (const char *name)
+void
+address_list_get_bounds (struct address_list *al, int *start, int *end)
{
- struct hostent *hp;
- unsigned long addr;
+ *start = al->faulty;
+ *end = al->count;
+}
- addr = (unsigned long)inet_addr (name);
- if ((int)addr != -1)
- hp = gethostbyaddr ((char *)&addr, sizeof (addr), AF_INET);
- else
- hp = gethostbyname (name);
- return hp;
+/* Copy address number INDEX to IP_STORE. */
+
+void
+address_list_copy_one (struct address_list *al, int index,
+ unsigned char *ip_store)
+{
+ assert (index >= al->faulty && index < al->count);
+ memcpy (ip_store, ADDR_LOCATION (al, index), IP4_ADDRESS_LENGTH);
}
-/* Search for HOST in the linked list L, by hostname. Return the
- entry, if found, or NULL. The search is case-insensitive. */
-static struct host *
-search_host (struct host *l, const char *host)
+/* Check whether two address lists have all their IPs in common. */
+
+int
+address_list_match_all (struct address_list *al1, struct address_list *al2)
{
- for (; l; l = l->next)
- if (strcasecmp (l->hostname, host) == 0)
- return l;
- return NULL;
+ if (al1 == al2)
+ return 1;
+ if (al1->count != al2->count)
+ return 0;
+ return 0 == memcmp (al1->buffer, al2->buffer,
+ al1->count * IP4_ADDRESS_LENGTH);
}
-/* Like search_host, but searches by address. */
-static struct host *
-search_address (struct host *l, const char *address)
+/* Mark the INDEXth element of AL as faulty, so that the next time
+ this address list is used, the faulty element will be skipped. */
+
+void
+address_list_set_faulty (struct address_list *al, int index)
{
- for (; l; l = l->next)
- {
- int cmp = strcmp (l->realname, address);
- if (cmp == 0)
- return l;
- else if (cmp > 0)
- return NULL;
- }
- return NULL;
+#if 0
+ /* Warning: INDEX is unused, so this assumes that the address list
+ is traversed in order. In the next release, either enable this
+ assert, or use INDEX. */
+ assert (index == al->faulty);
+#endif
+
+ ++al->faulty;
+ if (al->faulty >= al->count)
+ /* All addresses have been proven faulty. Since there's not much
+ sense in returning the user an empty address list the next
+ time, we'll rather make them all clean, so that they can be
+ retried anew. */
+ al->faulty = 0;
}
-/* Store the address of HOSTNAME, internet-style, to WHERE. First
- check for it in the host list, and (if not found), use
- ngethostbyname to get it.
+/* Create an address_list out of a NULL-terminated list of addresses,
+ as returned by gethostbyname. */
- Return 1 on successful finding of the hostname, 0 otherwise. */
-int
-store_hostaddress (unsigned char *where, const char *hostname)
+static struct address_list *
+address_list_new (char **h_addr_list)
{
- struct host *t;
- unsigned long addr;
- struct hostent *hptr;
- struct in_addr in;
- char *inet_s;
+ int count = 0, i;
- /* If the address is of the form d.d.d.d, there will be no trouble
- with it. */
- addr = (unsigned long)inet_addr (hostname);
- if ((int)addr == -1)
- {
- /* If it is not of that form, try to find it in the cache. */
- t = search_host (hlist, hostname);
- if (t)
- addr = (unsigned long)inet_addr (t->realname);
- }
- /* If we have the numeric address, just store it. */
- if ((int)addr != -1)
- {
- /* This works on both little and big endian architecture, as
- inet_addr returns the address in the proper order. */
-#ifdef WORDS_BIGENDIAN
- if (sizeof (addr) == 8)
- addr <<= 32;
-#endif
- memcpy (where, &addr, 4);
- return 1;
- }
- /* Since all else has failed, let's try gethostbyname(). Note that
- we use gethostbyname() rather than ngethostbyname(), because we
- *know* the address is not numerical. */
- hptr = gethostbyname (hostname);
- if (!hptr)
- return 0;
- /* Copy the address of the host to socket description. */
- memcpy (where, hptr->h_addr_list[0], hptr->h_length);
- /* Now that we're here, we could as well cache the hostname for
- future use, as in realhost(). First, we have to look for it by
- address to know if it's already in the cache by another name. */
-
- /* Originally, we copied to in.s_addr, but it appears to be missing
- on some systems. */
- memcpy (&in, *hptr->h_addr_list, sizeof (in));
- STRDUP_ALLOCA (inet_s, inet_ntoa (in));
- t = search_address (hlist, inet_s);
- if (t) /* Found in the list, as realname. */
- {
- /* Set the default, 0 quality. */
- hlist = add_hlist (hlist, hostname, inet_s, 0);
- return 1;
- }
- /* Since this is really the first time this host is encountered,
- set quality to 1. */
- hlist = add_hlist (hlist, hostname, inet_s, 1);
- return 1;
+ struct address_list *al = xmalloc (sizeof (struct address_list));
+
+ 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;
+
+ for (i = 0; i < count; i++)
+ memcpy (ADDR_LOCATION (al, i), h_addr_list[i], IP4_ADDRESS_LENGTH);
+
+ return al;
}
-/* Add a host to the host list. The list is sorted by addresses. For
- equal addresses, the entries with quality should bubble towards the
- beginning of the list. */
-static struct host *
-add_hlist (struct host *l, const char *nhost, const char *nreal, int quality)
+/* Like address_list_new, but initialized with only one address. */
+
+static struct address_list *
+address_list_new_one (const char *addr)
{
- struct host *t, *old, *beg;
+ struct address_list *al = xmalloc (sizeof (struct address_list));
+ al->count = 1;
+ al->faulty = 0;
+ al->buffer = xmalloc (IP4_ADDRESS_LENGTH);
+ al->refcount = 1;
+ memcpy (ADDR_LOCATION (al, 0), addr, IP4_ADDRESS_LENGTH);
+
+ return al;
+}
- /* The entry goes to the beginning of the list if the list is empty
- or the order requires it. */
- if (!l || (strcmp (nreal, l->realname) < 0))
- {
- t = (struct host *)xmalloc (sizeof (struct host));
- t->hostname = xstrdup (nhost);
- t->realname = xstrdup (nreal);
- t->quality = quality;
- t->next = l;
- return t;
- }
+static void
+address_list_delete (struct address_list *al)
+{
+ xfree (al->buffer);
+ xfree (al);
+}
- beg = l;
- /* Second two one-before-the-last element. */
- while (l->next)
+void
+address_list_release (struct address_list *al)
+{
+ --al->refcount;
+ DEBUGP (("Releasing %p (new refcount %d).\n", al, al->refcount));
+ if (al->refcount <= 0)
{
- int cmp;
- old = l;
- l = l->next;
- cmp = strcmp (nreal, l->realname);
- if (cmp >= 0)
- continue;
- /* If the next list element is greater than s, put s between the
- current and the next list element. */
- t = (struct host *)xmalloc (sizeof (struct host));
- old->next = t;
- t->next = l;
- t->hostname = xstrdup (nhost);
- t->realname = xstrdup (nreal);
- t->quality = quality;
- return beg;
+ DEBUGP (("Deleting unused %p.\n", al));
+ address_list_delete (al);
}
- t = (struct host *)xmalloc (sizeof (struct host));
- t->hostname = xstrdup (nhost);
- t->realname = xstrdup (nreal);
- t->quality = quality;
- /* Insert the new element after the last element. */
- l->next = t;
- t->next = NULL;
- return beg;
}
+\f
+/* The same as inet_ntoa, but without the need for a cast, or for
+ #including the netinet stuff. */
-/* Determine the "real" name of HOST, as perceived by Wget. If HOST
- is referenced by more than one name, "real" name is considered to
- be the first one encountered in the past.
-
- If the host cannot be found in the list of already dealt-with
- hosts, try with its INET address. If this fails too, add it to the
- list. The routine does not call gethostbyname twice for the same
- host if it can possibly avoid it. */
char *
-realhost (const char *host)
+pretty_print_address (const unsigned char *addr)
{
- struct host *l;
- struct in_addr in;
- struct hostent *hptr;
- char *inet_s;
+ return inet_ntoa (*(struct in_addr *)addr);
+}
- DEBUGP (("Checking for %s.\n", host));
- /* Look for the host, looking by the host name. */
- l = search_host (hlist, host);
- if (l && l->quality) /* Found it with quality */
- {
- DEBUGP (("%s was already used, by that name.\n", host));
- /* Here we return l->hostname, not host, because of the possible
- case differences (e.g. jaGOR.srce.hr and jagor.srce.hr are
- the same, but we want the one that was first. */
- return xstrdup (l->hostname);
- }
- else if (!l) /* Not found, with or without quality */
- {
- /* The fact that gethostbyname will get called makes it
- necessary to store it to the list, to ensure that
- gethostbyname will not be called twice for the same string.
- However, the quality argument must be set appropriately.
-
- Note that add_hlist must be called *after* the realname
- search, or the quality would be always set to 0 */
- DEBUGP (("This is the first time I hear about host %s by that name.\n",
- host));
- hptr = ngethostbyname (host);
- if (!hptr)
- return xstrdup (host);
- /* Originally, we copied to in.s_addr, but it appears to be
- missing on some systems. */
- memcpy (&in, *hptr->h_addr_list, sizeof (in));
- STRDUP_ALLOCA (inet_s, inet_ntoa (in));
- }
- else /* Found, without quality */
- {
- /* This case happens when host is on the list,
- but not as first entry (the one with quality).
- Then we just get its INET address and pick
- up the first entry with quality. */
- DEBUGP (("We've dealt with host %s, but under the name %s.\n",
- host, l->realname));
- STRDUP_ALLOCA (inet_s, l->realname);
- }
+/* 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. */
+
+static void
+cache_host_lookup (const char *host, struct address_list *al)
+{
+ if (!host_name_addresses_map)
+ host_name_addresses_map = make_nocase_string_hash_table (0);
- /* Now we certainly have the INET address. The following loop is
- guaranteed to pick either an entry with quality (because it is
- the first one), or none at all. */
- l = search_address (hlist, inet_s);
- if (l) /* Found in the list, as realname. */
+ ++al->refcount;
+ hash_table_put (host_name_addresses_map, xstrdup_lower (host), al);
+
+#ifdef DEBUG
+ if (opt.debug)
{
- /* Set the default, 0 quality. */
- hlist = add_hlist (hlist, host, inet_s, 0);
- return xstrdup (l->hostname);
+ 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 ("\n");
}
- /* Since this is really the first time this host is encountered,
- set quality to 1. */
- hlist = add_hlist (hlist, host, inet_s, 1);
- return xstrdup (host);
+#endif
}
-/* Compare two hostnames (out of URL-s if the arguments are URL-s),
- taking care of aliases. It uses realhost() to determine a unique
- hostname for each of two hosts. If simple_check is non-zero, only
- strcmp() is used for comparison. */
-int
-same_host (const char *u1, const char *u2)
+struct address_list *
+lookup_host (const char *host, int silent)
{
- const char *s;
- char *p1, *p2;
- char *real1, *real2;
-
- /* Skip protocol, if present. */
- u1 += skip_url (u1);
- u2 += skip_url (u2);
- u1 += skip_proto (u1);
- u2 += skip_proto (u2);
-
- /* Skip username ans password, if present. */
- u1 += skip_uname (u1);
- u2 += skip_uname (u2);
-
- for (s = u1; *u1 && *u1 != '/' && *u1 != ':'; u1++);
- p1 = strdupdelim (s, u1);
- for (s = u2; *u2 && *u2 != '/' && *u2 != ':'; u2++);
- p2 = strdupdelim (s, u2);
- DEBUGP (("Comparing hosts %s and %s...\n", p1, p2));
- if (strcasecmp (p1, p2) == 0)
- {
- free (p1);
- free (p2);
- DEBUGP (("They are quite alike.\n"));
- return 1;
- }
- else if (opt.simple_check)
+ 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)
{
- free (p1);
- free (p2);
- DEBUGP (("Since checking is simple, I'd say they are not the same.\n"));
- return 0;
+ /* 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;
+#else
+ offset = 0;
+#endif
+ return address_list_new_one ((char *)&addr + offset);
}
- real1 = realhost (p1);
- real2 = realhost (p2);
- free (p1);
- free (p2);
- if (strcasecmp (real1, real2) == 0)
+
+ /* 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);
+
+ if (al)
{
- DEBUGP (("They are alike, after realhost()->%s.\n", real1));
- free (real1);
- free (real2);
- return 1;
+ DEBUGP (("Found %s in host_name_addresses_map (%p)\n", host, al));
+ ++al->refcount;
+ return al;
}
- else
+
+ if (!silent)
+ logprintf (LOG_VERBOSE, _("Resolving %s... "), host);
+
+ /* Look up the host using gethostbyname(). */
+ hptr = gethostbyname (host);
+ if (!hptr)
{
- DEBUGP (("They are not the same (%s, %s).\n", real1, real2));
- free (real1);
- free (real2);
- return 0;
+ if (!silent)
+ logprintf (LOG_VERBOSE, _("failed: %s.\n"), herrmsg (h_errno));
+ return NULL;
}
-}
+ if (!silent)
+ logprintf (LOG_VERBOSE, _("done.\n"));
+
+ /* 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);
+
+ /* Cache the lookup information. */
+ cache_host_lookup (host, al);
+
+ return al;
+}
+\f
/* Determine whether a URL is acceptable to be followed, according to
a list of domains to accept. */
int
-accept_domain (struct urlinfo *u)
+accept_domain (struct url *u)
{
assert (u->host != NULL);
if (opt.domains)
return 0;
}
-/* Return email address of the form username@FQDN suitable for
- anonymous FTP passwords. This process is error-prone, and the
- escape hatch is the MY_HOST preprocessor constant, which can be
- used to hard-code either your hostname or FQDN at compile-time.
-
- If the FQDN cannot be determined, a warning is printed, and the
- function returns a short `username@' form, accepted by most
- anonymous servers.
-
- If not even the username cannot be divined, it means things are
- seriously fucked up, and Wget exits. */
-char *
-ftp_getaddress (void)
-{
- static char *address;
-
- /* Do the drill only the first time, as it won't change. */
- if (!address)
- {
- char userid[32]; /* 9 should be enough for Unix, but
- I'd rather be on the safe side. */
- char *host, *fqdn;
-
- if (!pwd_cuserid (userid))
- {
- logprintf (LOG_ALWAYS, _("%s: Cannot determine user-id.\n"),
- exec_name);
- exit (1);
- }
-#ifdef MY_HOST
- STRDUP_ALLOCA (host, MY_HOST);
-#else /* not MY_HOST */
-#ifdef HAVE_UNAME
- {
- struct utsname ubuf;
- if (uname (&ubuf) < 0)
- {
- logprintf (LOG_ALWAYS, _("%s: Warning: uname failed: %s\n"),
- exec_name, strerror (errno));
- fqdn = "";
- goto giveup;
- }
- STRDUP_ALLOCA (host, ubuf.nodename);
- }
-#else /* not HAVE_UNAME */
-#ifdef HAVE_GETHOSTNAME
- host = alloca (256);
- if (gethostname (host, 256) < 0)
- {
- logprintf (LOG_ALWAYS, _("%s: Warning: gethostname failed\n"),
- exec_name);
- fqdn = "";
- goto giveup;
- }
-#else /* not HAVE_GETHOSTNAME */
- #error Cannot determine host name.
-#endif /* not HAVE_GETHOSTNAME */
-#endif /* not HAVE_UNAME */
-#endif /* not MY_HOST */
- /* If the address we got so far contains a period, don't bother
- anymore. */
- if (strchr (host, '.'))
- fqdn = host;
- else
- {
- /* #### I've seen the following scheme fail on at least one
- system! Do we care? */
- char *tmpstore;
- /* According to Richard Stevens, the correct way to find the
- FQDN is to (1) find the host name, (2) find its IP
- address using gethostbyname(), and (3) get the FQDN using
- gethostbyaddr(). So that's what we'll do. Step one has
- been done above. */
- /* (2) */
- struct hostent *hp = gethostbyname (host);
- if (!hp || !hp->h_addr_list)
- {
- logprintf (LOG_ALWAYS, _("\
-%s: Warning: cannot determine local IP address.\n"),
- exec_name);
- fqdn = "";
- goto giveup;
- }
- /* Copy the argument, so the call to gethostbyaddr doesn't
- clobber it -- just in case. */
- tmpstore = (char *)alloca (hp->h_length);
- memcpy (tmpstore, *hp->h_addr_list, hp->h_length);
- /* (3) */
- hp = gethostbyaddr (tmpstore, hp->h_length, hp->h_addrtype);
- if (!hp || !hp->h_name)
- {
- logprintf (LOG_ALWAYS, _("\
-%s: Warning: cannot reverse-lookup local IP address.\n"),
- exec_name);
- fqdn = "";
- goto giveup;
- }
- if (!strchr (hp->h_name, '.'))
- {
-#if 0
- /* This gets ticked pretty often. Karl Berry reports
- that there can be valid reasons for the local host
- name not to be an FQDN, so I've decided to remove the
- annoying warning. */
- logprintf (LOG_ALWAYS, _("\
-%s: Warning: reverse-lookup of local address did not yield FQDN!\n"),
- exec_name);
-#endif
- fqdn = "";
- goto giveup;
- }
- /* Once we're here, hp->h_name contains the correct FQDN. */
- STRDUP_ALLOCA (fqdn, hp->h_name);
- }
- giveup:
- address = (char *)xmalloc (strlen (userid) + 1 + strlen (fqdn) + 1);
- sprintf (address, "%s@%s", userid, fqdn);
- }
- return address;
-}
-
/* Print error messages for host errors. */
char *
herrmsg (int error)
return _("Unknown error");
}
-/* Clean the host list. This is a separate function, so we needn't
- export HLIST and its implementation. Ha! */
-void
-clean_hosts (void)
+static int
+host_cleanup_mapper (void *key, void *value, void *arg_ignored)
{
- struct host *l = hlist;
+ struct address_list *al;
+
+ xfree (key); /* host */
- while (l)
+ al = (struct address_list *)value;
+ assert (al->refcount == 1);
+ address_list_delete (al);
+
+ return 0;
+}
+
+void
+host_cleanup (void)
+{
+ if (host_name_addresses_map)
{
- struct host *p = l->next;
- free (l->hostname);
- free (l->realname);
- free (l);
- l = p;
+ hash_table_map (host_name_addresses_map, host_cleanup_mapper, NULL);
+ hash_table_destroy (host_name_addresses_map);
+ host_name_addresses_map = NULL;
}
- hlist = NULL;
}
projects / wget / blobdiff