* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2016 */
+/* Copyright (c) University of Cambridge 1995 - 2017 */
/* See the file NOTICE for conditions of use and distribution. */
/* Functions for finding hosts, either by gethostbyname(), gethostbyaddr(), or
/* Host name is not verified */
-if (sender_host_name == NULL)
+if (!sender_host_name)
{
uschar *portptr = Ustrstr(address, "]:");
- int size = 0;
- int ptr = 0;
+ gstring * g;
int adlen; /* Sun compiler doesn't like ++ in initializers */
- adlen = (portptr == NULL)? Ustrlen(address) : (++portptr - address);
- sender_fullhost = (sender_helo_name == NULL)? address :
- string_sprintf("(%s) %s", sender_helo_name, address);
+ adlen = portptr ? (++portptr - address) : Ustrlen(address);
+ sender_fullhost = sender_helo_name
+ ? string_sprintf("(%s) %s", sender_helo_name, address)
+ : address;
- sender_rcvhost = string_catn(NULL, &size, &ptr, address, adlen);
+ g = string_catn(NULL, address, adlen);
if (sender_ident != NULL || show_helo || portptr != NULL)
{
int firstptr;
- sender_rcvhost = string_catn(sender_rcvhost, &size, &ptr, US" (", 2);
- firstptr = ptr;
+ g = string_catn(g, US" (", 2);
+ firstptr = g->ptr;
- if (portptr != NULL)
- sender_rcvhost = string_append(sender_rcvhost, &size, &ptr, 2, US"port=",
- portptr + 1);
+ if (portptr)
+ g = string_append(g, 2, US"port=", portptr + 1);
if (show_helo)
- sender_rcvhost = string_append(sender_rcvhost, &size, &ptr, 2,
- (firstptr == ptr)? US"helo=" : US" helo=", sender_helo_name);
+ g = string_append(g, 2,
+ firstptr == g->ptr ? US"helo=" : US" helo=", sender_helo_name);
- if (sender_ident != NULL)
- sender_rcvhost = string_append(sender_rcvhost, &size, &ptr, 2,
- (firstptr == ptr)? US"ident=" : US" ident=", sender_ident);
+ if (sender_ident)
+ g = string_append(g, 2,
+ firstptr == g->ptr ? US"ident=" : US" ident=", sender_ident);
- sender_rcvhost = string_catn(sender_rcvhost, &size, &ptr, US")", 1);
+ g = string_catn(g, US")", 1);
}
- sender_rcvhost[ptr] = 0; /* string_cat() always leaves room */
+ sender_rcvhost = string_from_gstring(g);
/* Release store, because string_cat allocated a minimum of 100 bytes that
are rarely completely used. */
- store_reset(sender_rcvhost + ptr + 1);
+ store_reset(sender_rcvhost + g->ptr + 1);
}
/* Host name is known and verified. Unless we've already found that the HELO
{
int sep = 0;
uschar *s;
-uschar buffer[64];
-ip_address_item *yield = NULL;
-ip_address_item *last = NULL;
-ip_address_item *next;
+ip_address_item * yield = NULL, * last = NULL, * next;
-while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL)
+while ((s = string_nextinlist(&list, &sep, NULL, 0)))
{
int ipv;
int port = host_address_extract_port(s); /* Leaves just the IP address */
- if ((ipv = string_is_ip_address(s, NULL)) == 0)
+
+ if (!(ipv = string_is_ip_address(s, NULL)))
log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Malformed IP address \"%s\" in %s",
s, name);
next->port = port;
next->v6_include_v4 = FALSE;
- if (yield == NULL) yield = last = next; else
+ if (!yield)
+ yield = last = next;
+ else
{
last->next = next;
last = next;
if (family == AF_INET6)
{
struct sockaddr_in6 *sk = (struct sockaddr_in6 *)arg;
- yield = (uschar *)inet_ntop(family, &(sk->sin6_addr), CS addr_buffer,
+ yield = US inet_ntop(family, &(sk->sin6_addr), CS addr_buffer,
sizeof(addr_buffer));
if (portptr != NULL) *portptr = ntohs(sk->sin6_port);
}
else
{
struct sockaddr_in *sk = (struct sockaddr_in *)arg;
- yield = (uschar *)inet_ntop(family, &(sk->sin_addr), CS addr_buffer,
+ yield = US inet_ntop(family, &(sk->sin_addr), CS addr_buffer,
sizeof(addr_buffer));
if (portptr != NULL) *portptr = ntohs(sk->sin_port);
}
}
else
{
- yield = (uschar *)inet_ntop(type, arg, CS addr_buffer, sizeof(addr_buffer));
+ yield = US inet_ntop(type, arg, CS addr_buffer, sizeof(addr_buffer));
}
/* If the result is a mapped IPv4 address, show it in V4 format. */
if (mask < 0)
*tt = 0;
else
- {
- sprintf(CS tt, "/%d", mask);
- while (*tt) tt++;
- }
+ tt += sprintf(CS tt, "/%d", mask);
return tt - buffer;
}
/* Copy and lowercase the name, which is in static storage in many systems.
Put it in permanent memory. */
-s = (uschar *)hosts->h_name;
+s = US hosts->h_name;
len = Ustrlen(s) + 1;
t = sender_host_name = store_get_perm(len);
while (*s != 0) *t++ = tolower(*s++);
truncated and dn_expand may fail. */
if (dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen,
- (uschar *)(rr->data), (DN_EXPAND_ARG4_TYPE)(s), ssize) < 0)
+ US (rr->data), (DN_EXPAND_ARG4_TYPE)(s), ssize) < 0)
{
log_write(0, LOG_MAIN, "host name alias list truncated for %s",
sender_host_address);
save_hostname = sender_host_name; /* Save for error messages */
aliases = sender_host_aliases;
-for (hname = sender_host_name; hname != NULL; hname = *aliases++)
+for (hname = sender_host_name; hname; hname = *aliases++)
{
int rc;
BOOL ok = FALSE;
d.request = sender_host_dnssec ? US"*" : NULL;;
d.require = NULL;
- if ( (rc = host_find_bydns(&h, NULL, HOST_FIND_BY_A,
+ if ( (rc = host_find_bydns(&h, NULL, HOST_FIND_BY_A | HOST_FIND_BY_AAAA,
NULL, NULL, NULL, &d, NULL, NULL)) == HOST_FOUND
|| rc == HOST_FOUND_LOCAL
)
h.dnssec == DS_YES ? "DNSSEC verified (AD)" : "unverified");
if (h.dnssec != DS_YES) sender_host_dnssec = FALSE;
- for (hh = &h; hh != NULL; hh = hh->next)
+ for (hh = &h; hh; hh = hh->next)
if (host_is_in_net(hh->address, sender_host_address, 0))
{
HDEBUG(D_host_lookup) debug_printf(" %s OK\n", hh->address);
if (hostdata->h_name[0] != 0 &&
Ustrcmp(host->name, hostdata->h_name) != 0)
- host->name = string_copy_dnsdomain((uschar *)hostdata->h_name);
+ host->name = string_copy_dnsdomain(US hostdata->h_name);
if (fully_qualified_name != NULL) *fully_qualified_name = host->name;
/* Get the list of addresses. IPv4 and IPv6 addresses can be distinguished
create additional host items for the additional addresses, copying all the
other fields, and randomizing the order.
-On IPv6 systems, A6 records are sought first (but only if support for A6 is
-configured - they may never become mainstream), then AAAA records are sought,
-and finally A records are sought as well.
+On IPv6 systems, AAAA records are sought first, then A records.
The host name may be changed if the DNS returns a different name - e.g. fully
qualified or changed via CNAME. If fully_qualified_name is not NULL, dns_lookup
to something)
dnssec_request if TRUE request the AD bit
dnssec_require if TRUE require the AD bit
+ whichrrs select ipv4, ipv6 results
Returns: HOST_FIND_FAILED couldn't find A record
HOST_FIND_AGAIN try again later
+ HOST_FIND_SECURITY dnssec required but not acheived
HOST_FOUND found AAAA and/or A record(s)
HOST_IGNORED found, but all IPs ignored
*/
set_address_from_dns(host_item *host, host_item **lastptr,
const uschar *ignore_target_hosts, BOOL allow_ip,
const uschar **fully_qualified_name,
- BOOL dnssec_request, BOOL dnssec_require)
+ BOOL dnssec_request, BOOL dnssec_require, int whichrrs)
{
dns_record *rr;
host_item *thishostlast = NULL; /* Indicates not yet filled in anything */
BOOL v6_find_again = FALSE;
+BOOL dnssec_fail = FALSE;
int i;
/* If allow_ip is set, a name which is an IP address returns that value
if (allow_ip && string_is_ip_address(host->name, NULL) != 0)
{
#ifndef STAND_ALONE
- if (ignore_target_hosts != NULL &&
- verify_check_this_host(&ignore_target_hosts, NULL, host->name,
+ if ( ignore_target_hosts
+ && verify_check_this_host(&ignore_target_hosts, NULL, host->name,
host->name, NULL) == OK)
return HOST_IGNORED;
#endif
}
/* On an IPv6 system, unless IPv6 is disabled, go round the loop up to twice,
-looking for AAAA records the first time. However, unless
-doing standalone testing, we force an IPv4 lookup if the domain matches
-dns_ipv4_lookup is set. On an IPv4 system, go round the
-loop once only, looking only for A records. */
+looking for AAAA records the first time. However, unless doing standalone
+testing, we force an IPv4 lookup if the domain matches dns_ipv4_lookup global.
+On an IPv4 system, go round the loop once only, looking only for A records. */
#if HAVE_IPV6
#ifndef STAND_ALONE
- if (disable_ipv6 || (dns_ipv4_lookup != NULL &&
- match_isinlist(host->name, CUSS &dns_ipv4_lookup, 0, NULL, NULL,
- MCL_DOMAIN, TRUE, NULL) == OK))
+ if ( disable_ipv6
+ || !(whichrrs & HOST_FIND_BY_AAAA)
+ || (dns_ipv4_lookup
+ && match_isinlist(host->name, CUSS &dns_ipv4_lookup, 0, NULL, NULL,
+ MCL_DOMAIN, TRUE, NULL) == OK)
+ )
i = 0; /* look up A records only */
else
#endif /* STAND_ALONE */
{
static int types[] = { T_A, T_AAAA };
int type = types[i];
- int randoffset = (i == 0)? 500 : 0; /* Ensures v6 sorts before v4 */
+ int randoffset = i == (whichrrs & HOST_FIND_IPV4_FIRST ? 1 : 0)
+ ? 500 : 0; /* Ensures v6/4 sort order */
dns_answer dnsa;
dns_scan dnss;
{
if (dnssec_require)
{
- log_write(L_host_lookup_failed, LOG_MAIN,
- "dnssec fail on %s for %.256s",
+ dnssec_fail = TRUE;
+ DEBUG(D_host_lookup) debug_printf("dnssec fail on %s for %.256s",
i>0 ? "AAAA" : "A", host->name);
continue;
}
}
}
-/* Control gets here only if the econdookup (the A record) succeeded.
+/* Control gets here only if the second lookup (the A record) succeeded.
However, the address may not be filled in if it was ignored. */
-return host->address ? HOST_FOUND : HOST_IGNORED;
+return host->address
+ ? HOST_FOUND
+ : dnssec_fail
+ ? HOST_FIND_SECURITY
+ : HOST_IGNORED;
}
whichrrs flags indicating which RRs to look for:
HOST_FIND_BY_SRV => look for SRV
HOST_FIND_BY_MX => look for MX
- HOST_FIND_BY_A => look for A or AAAA
+ HOST_FIND_BY_A => look for A
+ HOST_FIND_BY_AAAA => look for AAAA
also flags indicating how the lookup is done
HOST_FIND_QUALIFY_SINGLE ) passed to the
HOST_FIND_SEARCH_PARENTS ) resolver
+ HOST_FIND_IPV4_FIRST => reverse usual result ordering
+ HOST_FIND_IPV4_ONLY => MX results elide ipv6
srv_service when SRV used, the service name
srv_fail_domains DNS errors for these domains => assume nonexist
mx_fail_domains DNS errors for these domains => assume nonexist
if there was a syntax error,
host_find_failed_syntax is set.
HOST_FIND_AGAIN Could not resolve at this time
+ HOST_FIND_SECURITY dnsssec required but not acheived
HOST_FOUND Host found
HOST_FOUND_LOCAL The lowest MX record points to this
machine, if MX records were found, or
DEBUG(D_dns)
if ((dnssec_request || dnssec_require)
- & !dns_is_secure(&dnsa)
- & dns_is_aa(&dnsa))
+ && !dns_is_secure(&dnsa)
+ && dns_is_aa(&dnsa))
debug_printf("DNS lookup of %.256s (SRV) requested AD, but got AA\n", host->name);
if (dnssec_request)
records. On DNS failures, we give the "try again" error unless the domain is
listed as one for which we continue. */
-if (rc != DNS_SUCCEED && (whichrrs & HOST_FIND_BY_MX) != 0)
+if (rc != DNS_SUCCEED && whichrrs & HOST_FIND_BY_MX)
{
ind_type = T_MX;
dnssec = DS_UNK;
rc = dns_lookup_timerwrap(&dnsa, host->name, ind_type, fully_qualified_name);
DEBUG(D_dns)
- if ((dnssec_request || dnssec_require)
- & !dns_is_secure(&dnsa)
- & dns_is_aa(&dnsa))
+ if ( (dnssec_request || dnssec_require)
+ && !dns_is_secure(&dnsa)
+ && dns_is_aa(&dnsa))
debug_printf("DNS lookup of %.256s (MX) requested AD, but got AA\n", host->name);
if (dnssec_request)
- {
if (dns_is_secure(&dnsa))
{
DEBUG(D_host_lookup) debug_printf("%s MX DNSSEC\n", host->name);
{
dnssec = DS_NO; lookup_dnssec_authenticated = US"no";
}
- }
switch (rc)
{
case DNS_SUCCEED:
if (!dnssec_require || dns_is_secure(&dnsa))
break;
- log_write(L_host_lookup_failed, LOG_MAIN,
- "dnssec fail on MX for %.256s", host->name);
+ DEBUG(D_host_lookup)
+ debug_printf("dnssec fail on MX for %.256s", host->name);
+#ifndef STAND_ALONE
+ if (match_isinlist(host->name, CUSS &mx_fail_domains, 0, NULL, NULL,
+ MCL_DOMAIN, TRUE, NULL) != OK)
+ { yield = HOST_FIND_SECURITY; goto out; }
+#endif
rc = DNS_FAIL;
/*FALLTHROUGH*/
case DNS_FAIL:
case DNS_AGAIN:
- #ifndef STAND_ALONE
+#ifndef STAND_ALONE
if (match_isinlist(host->name, CUSS &mx_fail_domains, 0, NULL, NULL,
MCL_DOMAIN, TRUE, NULL) != OK)
- #endif
+#endif
{ yield = HOST_FIND_AGAIN; goto out; }
DEBUG(D_host_lookup) debug_printf("DNS_%s treated as DNS_NODATA "
"(domain in mx_fail_domains)\n", (rc == DNS_FAIL)? "FAIL":"AGAIN");
if (rc != DNS_SUCCEED)
{
- if ((whichrrs & HOST_FIND_BY_A) == 0)
+ if (!(whichrrs & (HOST_FIND_BY_A | HOST_FIND_BY_AAAA)))
{
DEBUG(D_host_lookup) debug_printf("Address records are not being sought\n");
yield = HOST_FIND_FAILED;
host->dnssec = DS_UNK;
lookup_dnssec_authenticated = NULL;
rc = set_address_from_dns(host, &last, ignore_target_hosts, FALSE,
- fully_qualified_name, dnssec_request, dnssec_require);
+ fully_qualified_name, dnssec_request, dnssec_require, whichrrs);
/* If one or more address records have been found, check that none of them
are local. Since we know the host items all have their IP addresses
if (h->address) continue; /* Inserted by a multihomed host */
rc = set_address_from_dns(h, &last, ignore_target_hosts, allow_mx_to_ip,
- NULL, dnssec_request, dnssec_require);
+ NULL, dnssec_request, dnssec_require,
+ whichrrs & HOST_FIND_IPV4_ONLY
+ ? HOST_FIND_BY_A : HOST_FIND_BY_A | HOST_FIND_BY_AAAA);
if (rc != HOST_FOUND)
{
h->status = hstatus_unusable;
- if (rc == HOST_FIND_AGAIN)
+ switch (rc)
{
- yield = rc;
- h->why = hwhy_deferred;
+ case HOST_FIND_AGAIN: yield = rc; h->why = hwhy_deferred; break;
+ case HOST_FIND_SECURITY: yield = rc; h->why = hwhy_insecure; break;
+ case HOST_IGNORED: h->why = hwhy_ignored; break;
+ default: h->why = hwhy_failed; break;
}
- else
- h->why = rc == HOST_IGNORED ? hwhy_ignored : hwhy_failed;
}
}
exist. If we end up with just a single, ignored host, flatten its fields as if
nothing was found. */
-if (ignore_target_hosts != NULL)
+if (ignore_target_hosts)
{
host_item *prev = NULL;
for (h = host; h != last->next; h = h->next)
addresses of a multihomed host, but that should not matter. */
#if HAVE_IPV6
-if (h != last && !disable_ipv6)
+if (h != last && !disable_ipv6) for (h = host; h != last; h = h->next)
{
- for (h = host; h != last; h = h->next)
- {
- host_item temp;
- host_item *next = h->next;
- if (h->mx != next->mx || /* If next is different MX */
- h->address == NULL || /* OR this one is unset */
- Ustrchr(h->address, ':') != NULL || /* OR this one is IPv6 */
- (next->address != NULL &&
- Ustrchr(next->address, ':') == NULL)) /* OR next is IPv4 */
- continue; /* move on to next */
- temp = *h; /* otherwise, swap */
- temp.next = next->next;
- *h = *next;
- h->next = next;
- *next = temp;
- }
+ host_item temp;
+ host_item *next = h->next;
+
+ if ( h->mx != next->mx /* If next is different MX */
+ || !h->address /* OR this one is unset */
+ )
+ continue; /* move on to next */
+
+ if ( whichrrs & HOST_FIND_IPV4_FIRST
+ ? !Ustrchr(h->address, ':') /* OR this one is IPv4 */
+ || next->address
+ && Ustrchr(next->address, ':') /* OR next is IPv6 */
+
+ : Ustrchr(h->address, ':') /* OR this one is IPv6 */
+ || next->address
+ && !Ustrchr(next->address, ':') /* OR next is IPv4 */
+ )
+ continue; /* move on to next */
+
+ temp = *h; /* otherwise, swap */
+ temp.next = next->next;
+ *h = *next;
+ h->next = next;
+ *next = temp;
}
#endif
debug_printf("host_find_bydns yield = %s (%d); returned hosts:\n",
(yield == HOST_FOUND)? "HOST_FOUND" :
(yield == HOST_FOUND_LOCAL)? "HOST_FOUND_LOCAL" :
+ (yield == HOST_FIND_SECURITY)? "HOST_FIND_SECURITY" :
(yield == HOST_FIND_AGAIN)? "HOST_FIND_AGAIN" :
(yield == HOST_FIND_FAILED)? "HOST_FIND_FAILED" : "?",
yield);
int main(int argc, char **cargv)
{
host_item h;
-int whichrrs = HOST_FIND_BY_MX | HOST_FIND_BY_A;
+int whichrrs = HOST_FIND_BY_MX | HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
BOOL byname = FALSE;
BOOL qualify_single = TRUE;
BOOL search_parents = FALSE;
if (Ustrcmp(buffer, "byname") == 0) byname = TRUE;
else if (Ustrcmp(buffer, "no_byname") == 0) byname = FALSE;
- else if (Ustrcmp(buffer, "a_only") == 0) whichrrs = HOST_FIND_BY_A;
+ else if (Ustrcmp(buffer, "a_only") == 0) whichrrs = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
else if (Ustrcmp(buffer, "mx_only") == 0) whichrrs = HOST_FIND_BY_MX;
else if (Ustrcmp(buffer, "srv_only") == 0) whichrrs = HOST_FIND_BY_SRV;
else if (Ustrcmp(buffer, "srv+a") == 0)
- whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_A;
+ whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
else if (Ustrcmp(buffer, "srv+mx") == 0)
whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX;
else if (Ustrcmp(buffer, "srv+mx+a") == 0)
- whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX | HOST_FIND_BY_A;
+ whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX | HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
else if (Ustrcmp(buffer, "qualify_single") == 0) qualify_single = TRUE;
else if (Ustrcmp(buffer, "no_qualify_single") == 0) qualify_single = FALSE;
else if (Ustrcmp(buffer, "search_parents") == 0) search_parents = TRUE;
else if (Ustrcmp(buffer, "request_dnssec") == 0) request_dnssec = TRUE;
else if (Ustrcmp(buffer, "no_request_dnssec") == 0) request_dnssec = FALSE;
else if (Ustrcmp(buffer, "require_dnssec") == 0) require_dnssec = TRUE;
- else if (Ustrcmp(buffer, "no_reqiret_dnssec") == 0) require_dnssec = FALSE;
+ else if (Ustrcmp(buffer, "no_require_dnssec") == 0) require_dnssec = FALSE;
else if (Ustrcmp(buffer, "test_harness") == 0)
running_in_test_harness = !running_in_test_harness;
else if (Ustrcmp(buffer, "ipv6") == 0) disable_ipv6 = !disable_ipv6;
: host_find_bydns(&h, NULL, flags, US"smtp", NULL, NULL,
&d, &fully_qualified_name, NULL);
- if (rc == HOST_FIND_FAILED) printf("Failed\n");
- else if (rc == HOST_FIND_AGAIN) printf("Again\n");
- else if (rc == HOST_FOUND_LOCAL) printf("Local\n");
+ switch (rc)
+ {
+ case HOST_FIND_FAILED: printf("Failed\n"); break;
+ case HOST_FIND_AGAIN: printf("Again\n"); break;
+ case HOST_FIND_SECURITY: printf("Security\n"); break;
+ case HOST_FOUND_LOCAL: printf("Local\n"); break;
+ }
}
printf("\n> ");