* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2017 */
+/* Copyright (c) University of Cambridge 1995 - 2018 */
/* See the file NOTICE for conditions of use and distribution. */
/* Functions for finding hosts, either by gethostbyname(), gethostbyaddr(), or
return 0;
if (random_seed == 0)
{
- if (running_in_test_harness) random_seed = 42; else
+ if (f.running_in_test_harness) random_seed = 42; else
{
int p = (int)getpid();
random_seed = (int)time(NULL) ^ ((p << 16) | p);
first place.
Because this data may survive over more than one incoming SMTP message, it has
-to be in permanent store.
+to be in permanent store. However, STARTTLS has to be forgotten and redone
+on a multi-message conn, so this will be called once per message then. Hence
+we use malloc, so we can free.
Arguments: none
Returns: nothing
host_build_sender_fullhost(void)
{
BOOL show_helo = TRUE;
-uschar *address;
+uschar * address, * fullhost, * rcvhost, * reset_point;
int len;
-int old_pool = store_pool;
-if (sender_host_address == NULL) return;
+if (!sender_host_address) return;
-store_pool = POOL_PERM;
+reset_point = store_get(0);
/* Set up address, with or without the port. After discussion, it seems that
the only format that doesn't cause trouble is [aaaa]:pppp. However, we can't
/* If there's no EHLO/HELO data, we can't show it. */
-if (sender_helo_name == NULL) show_helo = FALSE;
+if (!sender_helo_name) show_helo = FALSE;
/* If HELO/EHLO was followed by an IP literal, it's messy because of two
features of IPv6. Firstly, there's the "IPv6:" prefix (Exim is liberal and
int adlen; /* Sun compiler doesn't like ++ in initializers */
adlen = portptr ? (++portptr - address) : Ustrlen(address);
- sender_fullhost = sender_helo_name
+ fullhost = sender_helo_name
? string_sprintf("(%s) %s", sender_helo_name, address)
: address;
g = string_catn(NULL, address, adlen);
- if (sender_ident != NULL || show_helo || portptr != NULL)
+ if (sender_ident || show_helo || portptr)
{
int firstptr;
g = string_catn(g, US" (", 2);
g = string_catn(g, US")", 1);
}
- 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 + g->ptr + 1);
+ rcvhost = string_from_gstring(g);
}
/* Host name is known and verified. Unless we've already found that the HELO
if (show_helo)
{
- sender_fullhost = string_sprintf("%s (%s) %s", sender_host_name,
+ fullhost = string_sprintf("%s (%s) %s", sender_host_name,
sender_helo_name, address);
- sender_rcvhost = (sender_ident == NULL)?
- string_sprintf("%s (%s helo=%s)", sender_host_name,
- address, sender_helo_name) :
- string_sprintf("%s\n\t(%s helo=%s ident=%s)", sender_host_name,
- address, sender_helo_name, sender_ident);
+ rcvhost = sender_ident
+ ? string_sprintf("%s\n\t(%s helo=%s ident=%s)", sender_host_name,
+ address, sender_helo_name, sender_ident)
+ : string_sprintf("%s (%s helo=%s)", sender_host_name,
+ address, sender_helo_name);
}
else
{
- sender_fullhost = string_sprintf("%s %s", sender_host_name, address);
- sender_rcvhost = (sender_ident == NULL)?
- string_sprintf("%s (%s)", sender_host_name, address) :
- string_sprintf("%s (%s ident=%s)", sender_host_name, address,
- sender_ident);
+ fullhost = string_sprintf("%s %s", sender_host_name, address);
+ rcvhost = sender_ident
+ ? string_sprintf("%s (%s ident=%s)", sender_host_name, address,
+ sender_ident)
+ : string_sprintf("%s (%s)", sender_host_name, address);
}
}
-store_pool = old_pool;
+if (sender_fullhost) store_free(sender_fullhost);
+sender_fullhost = string_copy_malloc(fullhost);
+if (sender_rcvhost) store_free(sender_rcvhost);
+sender_rcvhost = string_copy_malloc(rcvhost);
+
+store_reset(reset_point);
DEBUG(D_host_lookup) debug_printf("sender_fullhost = %s\n", sender_fullhost);
DEBUG(D_host_lookup) debug_printf("sender_rcvhost = %s\n", sender_rcvhost);
/* For testing the case when a lookup does not complete, we have a special
reserved IP address. */
-if (running_in_test_harness &&
+if (f.running_in_test_harness &&
Ustrcmp(sender_host_address, "99.99.99.99") == 0)
{
HDEBUG(D_host_lookup)
/* If we have failed to find a name, return FAIL and log when required.
NB host_lookup_msg must be in permanent store. */
-if (sender_host_name == NULL)
+if (!sender_host_name)
{
- if (host_checking || !log_testing_mode)
+ if (host_checking || !f.log_testing_mode)
log_write(L_host_lookup_failed, LOG_MAIN, "no host name found for IP "
"address %s", sender_host_address);
host_lookup_msg = US" (failed to find host name from IP address)";
{
int rc;
BOOL ok = FALSE;
- host_item h;
- dnssec_domains d;
+ host_item h = { .next = NULL, .name = hname, .mx = MX_NONE, .address = NULL };
+ dnssec_domains d =
+ { .request = sender_host_dnssec ? US"*" : NULL, .require = NULL };
- h.next = NULL;
- h.name = hname;
- h.mx = MX_NONE;
- h.address = NULL;
- 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
)
/* Initialize the flag that gets set for DNS syntax check errors, so that the
interface to this function can be similar to host_find_bydns. */
-host_find_failed_syntax = FALSE;
+f.host_find_failed_syntax = FALSE;
/* Loop to look up both kinds of address in an IPv6 world */
if (slow_lookup_log) time_msec = get_time_in_ms();
#if HAVE_IPV6
- if (running_in_test_harness)
+ if (f.running_in_test_harness)
hostdata = host_fake_gethostbyname(host->name, af, &error_num);
else
{
}
#else /* not HAVE_IPV6 */
- if (running_in_test_harness)
+ if (f.running_in_test_harness)
hostdata = host_fake_gethostbyname(host->name, AF_INET, &error_num);
else
{
HDEBUG(D_host_lookup) debug_printf("%s\n", msg);
if (temp_error) goto RETURN_AGAIN;
- if (host_checking || !log_testing_mode)
+ if (host_checking || !f.log_testing_mode)
log_write(L_host_lookup_failed, LOG_MAIN, "%s", msg);
return HOST_FIND_FAILED;
}
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
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 */
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;
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
dns_init((whichrrs & HOST_FIND_QUALIFY_SINGLE) != 0,
(whichrrs & HOST_FIND_SEARCH_PARENTS) != 0,
dnssec_request);
-host_find_failed_syntax = FALSE;
+f.host_find_failed_syntax = FALSE;
/* First, if requested, look for SRV records. The service name is given; we
assume TCP protocol. DNS domain names are constrained to a maximum of 256
characters, so the code below should be safe. */
-if ((whichrrs & HOST_FIND_BY_SRV) != 0)
+if (whichrrs & HOST_FIND_BY_SRV)
{
- uschar buffer[300];
- uschar *temp_fully_qualified_name = buffer;
+ gstring * g;
+ uschar * temp_fully_qualified_name;
int prefix_length;
- (void)sprintf(CS buffer, "_%s._tcp.%n%.256s", srv_service, &prefix_length,
- host->name);
+ g = string_fmt_append(NULL, "_%s._tcp.%n%.256s",
+ srv_service, &prefix_length, host->name);
+ temp_fully_qualified_name = string_from_gstring(g);
ind_type = T_SRV;
/* Search for SRV records. If the fully qualified name is different to
dnssec = DS_UNK;
lookup_dnssec_authenticated = NULL;
- rc = dns_lookup_timerwrap(&dnsa, buffer, ind_type, CUSS &temp_fully_qualified_name);
+ rc = dns_lookup_timerwrap(&dnsa, temp_fully_qualified_name, ind_type,
+ CUSS &temp_fully_qualified_name);
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)
{ dnssec = DS_NO; lookup_dnssec_authenticated = US"no"; }
}
- if (temp_fully_qualified_name != buffer && fully_qualified_name != NULL)
+ if (temp_fully_qualified_name != g->s && fully_qualified_name != NULL)
*fully_qualified_name = temp_fully_qualified_name + prefix_length;
/* On DNS failures, we give the "try again" error unless the domain is
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
rr;
rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) if (rr->type == ind_type)
{
- int precedence;
- int weight = 0; /* For SRV records */
+ int precedence, weight;
int port = PORT_NONE;
const uschar * s = rr->data; /* MUST be unsigned for GETSHORT */
uschar data[256];
if (ind_type == T_MX)
weight = random_number(500);
-
- /* SRV records are specified with a port and a weight. The weight is used
- in a special algorithm. However, to start with, we just use it to order the
- records of equal priority (precedence). */
-
else
{
+ /* SRV records are specified with a port and a weight. The weight is used
+ in a special algorithm. However, to start with, we just use it to order the
+ records of equal priority (precedence). */
GETSHORT(weight, s);
GETSHORT(port, s);
}
never know what junk might get into the DNS (and this case has been seen on
more than one occasion). */
- if (last != NULL) /* This is not the first record */
+ if (last) /* This is not the first record */
{
host_item *prev = NULL;
for (h = host; h != last->next; prev = h, h = h->next)
- {
if (strcmpic(h->name, data) == 0)
{
DEBUG(D_host_lookup)
debug_printf("discarded duplicate host %s (MX=%d)\n", data,
- (precedence > h->mx)? precedence : h->mx);
+ precedence > h->mx ? precedence : h->mx);
if (precedence >= h->mx) goto NEXT_MX_RR; /* Skip greater precedence */
if (h == host) /* Override first item */
{
if (h == last) last = prev;
break;
}
- }
}
/* If this is the first MX or SRV record, put the data into the existing host
block. Otherwise, add a new block in the correct place; if it has to be
before the first block, copy the first block's data to a new second block. */
- if (last == NULL)
+ if (!last)
{
host->name = string_copy_dnsdomain(data);
host->address = NULL;
host->dnssec = dnssec;
last = host;
}
+ else
/* Make a new host item and seek the correct insertion place */
-
- else
{
int sort_key = precedence * 1000 + weight;
host_item *next = store_get(sizeof(host_item));
host->next = next;
if (last == host) last = next;
}
+ else
/* Else scan down the items we have inserted as part of this exercise;
don't go further. */
-
- else
{
for (h = host; h != last; h = h->next)
- {
if (sort_key < h->next->sort_key)
{
next->next = h->next;
h->next = next;
break;
}
- }
/* Join on after the last host item that's part of this
processing if we haven't stopped sooner. */
for (ppptr = pptr, hhh = h;
hhh != hh;
- ppptr = &(hhh->next), hhh = hhh->next)
- {
- if (hhh->sort_key >= randomizer) break;
- }
+ ppptr = &hhh->next, hhh = hhh->next)
+ if (hhh->sort_key >= randomizer)
+ break;
/* hhh now points to the host that should go first; ppptr points to the
place that points to it. Unfortunately, if the start of the minilist is
hhh->next = temp.next;
h->next = hhh;
}
-
else
{
hhh->next = h; /* The rest of the chain follows it */
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;
switch (rc)
{
- 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;
+ 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;
}
}
}
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 */
+ 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;
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, "require_dnssec") == 0) require_dnssec = TRUE;
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;
+ f.running_in_test_harness = !f.running_in_test_harness;
else if (Ustrcmp(buffer, "ipv6") == 0) disable_ipv6 = !disable_ipv6;
else if (Ustrcmp(buffer, "res_debug") == 0)
{
projects / exim.git / blobdiff