static void
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 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 (al->addresses + i));
debug_logprintf ("\n");
}
#endif
}
struct address_list *
lookup_host (const char *host, int flags)
{
struct address_list *al;
int silent = flags & LH_SILENT;
int use_cache;
int numeric_address = 0;
double timeout = opt.dns_timeout;
#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 = 1;
}
#endif
/* 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 = 0;
#endif
/* 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)
{
if (!(flags & LH_REFRESH))
{
al = cache_query (host);
if (al)
return al;
}
else
cache_remove (host);
}
/* No luck with the cache; resolve HOST. */
if (!silent && !numeric_address)
logprintf (LOG_VERBOSE, _("Resolving %s... "), escnonprint (host));
#ifdef ENABLE_IPV6
{
int err;
struct addrinfo hints, *res;
xzero (hints);
hints.ai_socktype = SOCK_STREAM;
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
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));
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;
}
/* 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 /* not ENABLE_IPV6 */
{
struct hostent *hptr = gethostbyname_with_timeout (host, timeout);
if (!hptr)
{
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 older systems have h_addr_list? */
al = address_list_from_ipv4_addresses (hptr->h_addr_list);
}
#endif /* not ENABLE_IPV6 */
/* 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++)
{
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");
}
/* Cache the lookup information. */
if (use_cache)
cache_store (host, al);
return al;
}
struct address_list *
lookup_host (const char *host, int silent)
{
struct address_list *al = NULL;
uint32_t addr_ipv4;
ip_address addr;
/* First, try to check whether the address is already a numeric
address. */
#ifdef ENABLE_IPV6
if (inet_pton (AF_INET6, host, &addr) > 0)
return address_list_from_single (&addr);
#endif
addr_ipv4 = (uint32_t)inet_addr (host);
if (addr_ipv4 != (uint32_t)-1)
{
/* ADDR is defined to be in network byte order, which is what
this returns, so we can just copy it to STORE_IP. */
map_ipv4_to_ip ((ip4_address *)&addr_ipv4, &addr);
return address_list_from_single (&addr);
}
if (host_name_addresses_map)
{
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 (!silent)
logprintf (LOG_VERBOSE, _("Resolving %s... "), host);
/* Host name lookup goes on below. */
#ifdef HAVE_GETADDRINFO
{
struct addrinfo hints, *ai;
int err;
memset (&hints, 0, sizeof (hints));
if (ip_default_family == AF_INET)
hints.ai_family = AF_INET;
else
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_STREAM;
err = getaddrinfo_with_timeout (host, NULL, &hints, &ai, opt.dns_timeout);
if (err != 0 || ai == NULL)
{
if (!silent)
logprintf (LOG_VERBOSE, _("failed: %s.\n"),
err != EAI_SYSTEM ? gai_strerror (err) : strerror (errno));
return NULL;
}
al = address_list_from_addrinfo (ai);
freeaddrinfo (ai);
}
#else
{
struct hostent *hptr;
hptr = gethostbyname_with_timeout (host, opt.dns_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;
}
/* Do all systems have h_addr_list, or is it a newer thing? If
the latter, use address_list_from_single. */
al = address_list_from_vector (hptr->h_addr_list);
}
#endif
/* Print the addresses determined by DNS lookup, but no more than
three. */
if (!silent)
{
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");
}
/* Cache the lookup information. */
if (opt.dns_cache)
cache_host_lookup (host, al);
return al;
}
