* Exim - an Internet mail transport agent *
*************************************************/
+/* Copyright (c) The Exim Maintainers 2020 - 2022 */
/* Copyright (c) University of Cambridge 1995 - 2018 */
/* See the file NOTICE for conditions of use and distribution. */
+/* SPDX-License-Identifier: GPL-2.0-or-later */
#include "../exim.h"
#include "lf_functions.h"
/* See local README for interface description. */
static void *
-dnsdb_open(uschar *filename, uschar **errmsg)
+dnsdb_open(const uschar * filename, uschar **errmsg)
{
-filename = filename; /* Keep picky compilers happy */
-errmsg = errmsg; /* Ditto */
return (void *)(-1); /* Any non-0 value */
}
causes the whole lookup to defer only if none of the DNS queries succeeds; and
'never', where all defers are as if the lookup failed. The default is 'lax'.
-- 'dnssec_FOO', with 'strict', 'lax' and 'never' (default). The meanings are
+- 'dnssec_FOO', with 'strict', 'lax' (default), and 'never'. The meanings are
require, try and don't-try dnssec respectively.
- 'retrans_VAL', set the timeout value. VAL is an Exim time specification
separator, as always, is colon. */
static int
-dnsdb_find(void *handle, uschar *filename, const uschar *keystring, int length,
- uschar **result, uschar **errmsg, uint *do_cache)
+dnsdb_find(void * handle, const uschar * filename, const uschar * keystring,
+ int length, uschar ** result, uschar ** errmsg, uint * do_cache,
+ const uschar * opts)
{
int rc;
int sep = 0;
-int defer_mode = PASS;
-int dnssec_mode = OK;
-int save_retrans = dns_retrans;
-int save_retry = dns_retry;
+int defer_mode = PASS, dnssec_mode = PASS;
+int save_retrans = dns_retrans, save_retry = dns_retry;
int type;
int failrc = FAIL;
-const uschar *outsep = CUS"\n";
-const uschar *outsep2 = NULL;
-uschar *equals, *domain, *found;
+const uschar * outsep = CUS"\n", * outsep2 = NULL;
+uschar * equals, * domain, * found;
+
+dns_answer * dnsa = store_get_dns_answer();
+dns_scan dnss;
/* Because we're working in the search pool, we try to reclaim as much
store as possible later, so we preallocate the result here */
gstring * yield = string_get(256);
-dns_record * rr;
-dns_answer dnsa;
-dns_scan dnss;
-
-handle = handle; /* Keep picky compilers happy */
-filename = filename;
-length = length;
-do_cache = do_cache;
-
/* If the string starts with '>' we change the output separator.
If it's followed by ';' or ',' we set the TXT output separator. */
else
{
*errmsg = US"unsupported dnsdb defer behaviour";
- return DEFER;
+ rc = DEFER;
+ goto out;
}
}
else if (strncmpic(keystring, US"dnssec_", 7) == 0)
else
{
*errmsg = US"unsupported dnsdb dnssec behaviour";
- return DEFER;
+ rc = DEFER;
+ goto out;
}
}
else if (strncmpic(keystring, US"retrans_", 8) == 0)
if ((timeout_sec = readconf_readtime(keystring += 8, ',', FALSE)) <= 0)
{
*errmsg = US"unsupported dnsdb timeout value";
- return DEFER;
+ rc = DEFER;
+ goto out;
}
dns_retrans = timeout_sec;
while (*keystring != ',') keystring++;
if ((retries = (int)strtol(CCS keystring + 6, CSS &keystring, 0)) < 0)
{
*errmsg = US"unsupported dnsdb retry count";
- return DEFER;
+ rc = DEFER;
+ goto out;
}
dns_retry = retries;
}
if (*keystring++ != ',')
{
*errmsg = US"dnsdb modifier syntax error";
- return DEFER;
+ rc = DEFER;
+ goto out;
}
while (isspace(*keystring)) keystring++;
}
if (i >= nelem(type_names))
{
*errmsg = US"unsupported DNS record type";
- return DEFER;
+ rc = DEFER;
+ goto out;
}
keystring = equals + 1;
while ((domain = string_nextinlist(&keystring, &sep, NULL, 0)))
{
- uschar rbuffer[256];
- int searchtype = (type == T_CSA)? T_SRV : /* record type we want */
- (type == T_MXH)? T_MX :
- (type == T_ZNS)? T_NS : type;
+ int searchtype = type == T_CSA ? T_SRV : /* record type we want */
+ type == T_MXH ? T_MX :
+ type == T_ZNS ? T_NS : type;
/* If the type is PTR or CSA, we have to construct the relevant magic lookup
key if the original is an IP address (some experimental protocols are using
if ((type == T_PTR || type == T_CSA) &&
string_is_ip_address(domain, NULL) != 0)
- {
- dns_build_reverse(domain, rbuffer);
- domain = rbuffer;
- }
+ domain = dns_build_reverse(domain);
do
{
- DEBUG(D_lookup) debug_printf("dnsdb key: %s\n", domain);
+ DEBUG(D_lookup) debug_printf_indent("dnsdb key: %s\n", domain);
/* Do the lookup and sort out the result. There are four special types that
are handled specially: T_CSA, T_ZNS, T_ADDRESSES and T_MXH.
{
if (searchtype == T_ADDRESSES) searchtype = T_AAAA;
else if (searchtype == T_AAAA) searchtype = T_A;
- rc = dns_special_lookup(&dnsa, domain, searchtype, CUSS &found);
+ rc = dns_special_lookup(dnsa, domain, searchtype, CUSS &found);
}
else
#endif
- rc = dns_special_lookup(&dnsa, domain, type, CUSS &found);
+ rc = dns_special_lookup(dnsa, domain, type, CUSS &found);
lookup_dnssec_authenticated = dnssec_mode==OK ? NULL
- : dns_is_secure(&dnsa) ? US"yes" : US"no";
+ : dns_is_secure(dnsa) ? US"yes" : US"no";
if (rc == DNS_NOMATCH || rc == DNS_NODATA) continue;
if ( rc != DNS_SUCCEED
- || (dnssec_mode == DEFER && !dns_is_secure(&dnsa))
+ || (dnssec_mode == DEFER && !dns_is_secure(dnsa))
)
{
if (defer_mode == DEFER)
dns_retrans = save_retrans;
dns_retry = save_retry;
dns_init(FALSE, FALSE, FALSE); /* clr dnssec bit */
- return DEFER; /* always defer */
+ rc = DEFER; /* always defer */
+ goto out;
}
if (defer_mode == PASS) failrc = DEFER; /* defer only if all do */
continue; /* treat defer as fail */
/* Search the returned records */
- for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); rr;
- rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) if (rr->type == searchtype)
+ for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == searchtype)
{
if (*do_cache > rr->ttl)
*do_cache = rr->ttl;
if (type == T_A || type == T_AAAA || type == T_ADDRESSES)
{
- dns_address *da;
- for (da = dns_address_from_rr(&dnsa, rr); da; da = da->next)
- {
- if (yield->ptr) yield = string_catn(yield, outsep, 1);
- yield = string_cat(yield, da->address);
- }
+ for (dns_address * da = dns_address_from_rr(dnsa, rr); da; da = da->next)
+ yield = string_append_listele(yield, *outsep, da->address);
continue;
}
if (type == T_TXT || type == T_SPF)
{
- if (outsep2 == NULL) /* output only the first item of data */
+ if (!outsep2) /* output only the first item of data */
yield = string_catn(yield, US (rr->data+1), (rr->data)[0]);
else
- {
- /* output all items */
- int data_offset = 0;
- while (data_offset < rr->size)
+ for (unsigned data_offset = 0; data_offset < rr->size; )
{
- uschar chunk_len = (rr->data)[data_offset++];
- if (outsep2[0] != '\0' && data_offset != 1)
+ uschar chunk_len = (rr->data)[data_offset];
+ if (*outsep2 && data_offset != 0)
yield = string_catn(yield, outsep2, 1);
- yield = string_catn(yield, US ((rr->data)+data_offset), chunk_len);
+ yield = string_catn(yield, US ((rr->data) + ++data_offset), chunk_len);
data_offset += chunk_len;
}
- }
}
else if (type == T_TLSA)
{
/* GETSHORT() has advanced the pointer to the target domain. */
- rc = dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
+ rc = dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen, p,
(DN_EXPAND_ARG4_TYPE)s, sizeof(s));
/* If an overlong response was received, the data will have been
p += rc;
yield = string_catn(yield, outsep2, 1);
- rc = dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
+ rc = dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen, p,
(DN_EXPAND_ARG4_TYPE)s, sizeof(s));
if (rc < 0)
{
/* Reclaim unused memory */
-store_reset(yield->s + yield->ptr + 1);
+gstring_release_unused(yield);
/* If yield NULL we have not found anything. Otherwise, insert the terminating
zero and return the result. */
dns_retry = save_retry;
dns_init(FALSE, FALSE, FALSE); /* clear the dnssec bit for getaddrbyname */
-if (!yield || !yield->ptr) return failrc;
+if (!yield || !yield->ptr)
+ rc = failrc;
+else
+ {
+ *result = string_from_gstring(yield);
+ rc = OK;
+ }
+
+out:
-*result = string_from_gstring(yield);
-return OK;
+store_free_dns_answer(dnsa);
+return rc;
}
#include "../version.h"
-void
-dnsdb_version_report(FILE *f)
+gstring *
+dnsdb_version_report(gstring * g)
{
#ifdef DYNLOOKUP
-fprintf(f, "Library version: DNSDB: Exim version %s\n", EXIM_VERSION_STR);
+g = string_fmt_append(g, "Library version: DNSDB: Exim version %s\n", EXIM_VERSION_STR);
#endif
+return g;
}
static lookup_info _lookup_info = {
- US"dnsdb", /* lookup name */
- lookup_querystyle, /* query style */
- dnsdb_open, /* open function */
- NULL, /* check function */
- dnsdb_find, /* find function */
- NULL, /* no close function */
- NULL, /* no tidy function */
- NULL, /* no quoting function */
- dnsdb_version_report /* version reporting */
+ .name = US"dnsdb", /* lookup name */
+ .type = lookup_querystyle, /* query style */
+ .open = dnsdb_open, /* open function */
+ .check = NULL, /* check function */
+ .find = dnsdb_find, /* find function */
+ .close = NULL, /* no close function */
+ .tidy = NULL, /* no tidy function */
+ .quote = NULL, /* no quoting function */
+ .version_report = dnsdb_version_report /* version reporting */
};
#ifdef DYNLOOKUP