* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2014 */
+/* Copyright (c) University of Cambridge 1995 - 2015 */
/* See the file NOTICE for conditions of use and distribution. */
/* Functions concerned with verifying things. The original code for callout
/* Structure for caching DNSBL lookups */
typedef struct dnsbl_cache_block {
+ time_t expiry;
dns_address *rhs;
uschar *text;
int rc;
host_af = (Ustrchr(host->address, ':') == NULL)? AF_INET:AF_INET6;
- if (!smtp_get_interface(tf->interface, host_af, addr, NULL, &interface,
+ if (!smtp_get_interface(tf->interface, host_af, addr, &interface,
US"callout") ||
!smtp_get_port(tf->port, addr, &port, US"callout"))
log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
deliver_domain = addr->domain;
transport_name = addr->transport->name;
- if ( !smtp_get_interface(tf->interface, host_af, addr, NULL, &interface,
+ if ( !smtp_get_interface(tf->interface, host_af, addr, &interface,
US"callout")
|| !smtp_get_port(tf->port, addr, &port, US"callout")
)
(void)host_find_byname(host, NULL, flags, NULL, TRUE);
else
{
- uschar * d_request = NULL, * d_require = NULL;
+ dnssec_domains * dnssec_domains = NULL;
if (Ustrcmp(addr->transport->driver_name, "smtp") == 0)
{
smtp_transport_options_block * ob =
(smtp_transport_options_block *)
addr->transport->options_block;
- d_request = ob->dnssec_request_domains;
- d_require = ob->dnssec_require_domains;
+ dnssec_domains = &ob->dnssec;
}
(void)host_find_bydns(host, NULL, flags, NULL, NULL, NULL,
- d_request, d_require, NULL, NULL);
+ dnssec_domains, NULL, NULL);
}
}
}
if (ip_connect(sock, host_af, sender_host_address, port, rfc1413_query_timeout)
< 0)
{
- if (errno == ETIMEDOUT && (log_extra_selector & LX_ident_timeout) != 0)
+ if (errno == ETIMEDOUT && LOGGING(ident_timeout))
{
log_write(0, LOG_MAIN, "ident connection to %s timed out",
sender_host_address);
h.address = NULL;
h.mx = MX_NONE;
+ /* Using byname rather than bydns here means we cannot determine dnssec
+ status. On the other hand it is unclear how that could be either
+ propagated up or enforced. */
+
rc = host_find_byname(&h, NULL, HOST_FIND_QUALIFY_SINGLE, NULL, FALSE);
if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL)
{
/* Look for this query in the cache. */
-t = tree_search(dnsbl_cache, query);
+if ( (t = tree_search(dnsbl_cache, query))
+ && (cb = t->data.ptr)->expiry > time(NULL)
+ )
+
+/* Previous lookup was cached */
+
+ {
+ HDEBUG(D_dnsbl) debug_printf("using result of previous DNS lookup\n");
+ }
/* If not cached from a previous lookup, we must do a DNS lookup, and
cache the result in permanent memory. */
-if (t == NULL)
+else
{
+ uint ttl = 3600;
+
store_pool = POOL_PERM;
- /* Set up a tree entry to cache the lookup */
+ if (t)
+ {
+ HDEBUG(D_dnsbl) debug_printf("cached data found but past valid time; ");
+ }
- t = store_get(sizeof(tree_node) + Ustrlen(query));
- Ustrcpy(t->name, query);
- t->data.ptr = cb = store_get(sizeof(dnsbl_cache_block));
- (void)tree_insertnode(&dnsbl_cache, t);
+ else
+ { /* Set up a tree entry to cache the lookup */
+ t = store_get(sizeof(tree_node) + Ustrlen(query));
+ Ustrcpy(t->name, query);
+ t->data.ptr = cb = store_get(sizeof(dnsbl_cache_block));
+ (void)tree_insertnode(&dnsbl_cache, t);
+ }
/* Do the DNS loopup . */
Quite apart from one A6 RR generating multiple addresses, there are DNS
lists that return more than one A record, so we must handle multiple
- addresses generated in that way as well. */
+ addresses generated in that way as well.
+
+ Mark the cache entry with the "now" plus the minimum of the address TTLs,
+ or some suitably far-future time if none were found. */
if (cb->rc == DNS_SUCCEED)
{
dns_record *rr;
dns_address **addrp = &(cb->rhs);
for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
- rr != NULL;
+ rr;
rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
{
if (rr->type == T_A)
{
dns_address *da = dns_address_from_rr(&dnsa, rr);
- if (da != NULL)
+ if (da)
{
*addrp = da;
while (da->next != NULL) da = da->next;
addrp = &(da->next);
+ if (ttl > rr->ttl) ttl = rr->ttl;
}
}
}
if (cb->rhs == NULL) cb->rc = DNS_NODATA;
}
+ cb->expiry = time(NULL)+ttl;
store_pool = old_pool;
}
-/* Previous lookup was cached */
-
-else
- {
- HDEBUG(D_dnsbl) debug_printf("using result of previous DNS lookup\n");
- cb = t->data.ptr;
- }
-
/* We now have the result of the DNS lookup, either newly done, or cached
from a previous call. If the lookup succeeded, check against the address
list if there is one. This may be a positive equality list (introduced by