-/* $Cambridge: exim/src/src/lookups/dnsdb.c,v 1.13 2005/06/10 13:38:06 tom Exp $ */
-
/*************************************************
* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2005 */
+/* Copyright (c) The Exim Maintainers 2020 - 2024 */
+/* 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"
-#include "dnsdb.h"
header files. */
#ifndef T_TXT
-#define T_TXT 16
+# define T_TXT 16
+#endif
+
+/* Many systems do not have T_SPF. */
+#ifndef T_SPF
+# define T_SPF 99
+#endif
+
+/* New TLSA record for DANE */
+#ifndef T_TLSA
+# define T_TLSA 52
#endif
/* Table of recognized DNS record types and their integer values. */
-static char *type_names[] = {
+static const char *type_names[] = {
"a",
#if HAVE_IPV6
+ "a+",
"aaaa",
- #ifdef SUPPORT_A6
- "a6",
- #endif
#endif
"cname",
"csa",
"mxh",
"ns",
"ptr",
+ "soa",
+ "spf",
"srv",
+ "tlsa",
"txt",
"zns"
};
static int type_values[] = {
T_A,
#if HAVE_IPV6
+ T_ADDRESSES, /* Private type for AAAA + A */
T_AAAA,
- #ifdef SUPPORT_A6
- T_A6,
- #endif
#endif
T_CNAME,
T_CSA, /* Private type for "Client SMTP Authorization". */
T_MXH, /* Private type for "MX hostnames" */
T_NS,
T_PTR,
+ T_SOA,
+ T_SPF,
T_SRV,
+ T_TLSA,
T_TXT,
T_ZNS /* Private type for "zone nameservers" */
};
/* See local README for interface description. */
-void *
-dnsdb_open(uschar *filename, uschar **errmsg)
+static void *
+dnsdb_open(const uschar * filename, uschar **errmsg)
{
-filename = filename; /* Keep picky compilers happy */
-errmsg = errmsg; /* Ditto */
return (void *)(-1); /* Any non-0 value */
}
separator character that is used when multiple records are found. The default
separator is newline.
-(b) If the next sequence of characters is 'defer_FOO' followed by a comma,
-the defer behaviour is set to FOO. The possible behaviours are: 'strict', where
-any defer causes the whole lookup to defer; 'lax', where a defer 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'.
+(b) If the next character is ',' then the next character is the separator
+character used for multiple items of text in "TXT" records. Alternatively,
+if the next character is ';' then these multiple items are concatenated with
+no separator. With neither of these options specified, only the first item
+is output. Similarly for "SPF" records, but the default for joining multiple
+items in one SPF record is the empty string, for direct concatenation.
+
+(c) Options, all comma-terminated, in any order. Any unrecognised option
+terminates option processing. Recognised options are:
-(c) If the next sequence of characters is a sequence of letters and digits
+- 'defer_FOO': set the defer behaviour to FOO. The possible behaviours are:
+'strict', where any defer causes the whole lookup to defer; 'lax', where a defer
+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' (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
+(eg "5s"). The default is set by the main configuration option 'dns_retrans'.
+
+- 'retry_VAL', set the retry count on timeouts. VAL is an integer. The
+default is set by the main configuration option "dns_retry".
+
+(d) If the next sequence of characters is a sequence of letters and digits
followed by '=', it is interpreted as the name of the DNS record type. The
default is "TXT".
-(d) Then there follows list of domain names. This is a generalized Exim list,
+(e) Then there follows list of domain names. This is a generalized Exim list,
which may start with '<' in order to set a specific separator. The default
separator, as always, is colon. */
-int
-dnsdb_find(void *handle, uschar *filename, uschar *keystring, int length,
- uschar **result, uschar **errmsg, BOOL *do_cache)
+static int
+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 size = 256;
-int ptr = 0;
int sep = 0;
-int defer_mode = PASS;
-int type = T_TXT;
+int defer_mode = PASS, dnssec_mode = PASS;
+int save_retrans = dns_retrans, save_retry = dns_retry;
+int type;
int failrc = FAIL;
-uschar *outsep = US"\n";
-uschar *equals, *domain, *found;
-uschar buffer[256];
-
-/* Because we're the working in the search pool, we try to reclaim as much
-store as possible later, so we preallocate the result here */
-
-uschar *yield = store_get(size);
+const uschar * outsep = CUS"\n", * outsep2 = NULL;
+uschar * equals, * domain, * found;
-dns_record *rr;
-dns_answer dnsa;
+dns_answer * dnsa = store_get_dns_answer();
dns_scan dnss;
-handle = handle; /* Keep picky compilers happy */
-filename = filename;
-length = length;
-do_cache = do_cache;
+/* 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);
-/* If the string starts with '>' we change the output separator */
+/* If the string starts with '>' we change the output separator.
+If it's followed by ';' or ',' we set the TXT output separator. */
-while (isspace(*keystring)) keystring++;
-if (*keystring == '>')
+if (Uskip_whitespace(&keystring) == '>')
{
outsep = keystring + 1;
keystring += 2;
- while (isspace(*keystring)) keystring++;
+ if (*keystring == ',')
+ {
+ outsep2 = keystring + 1;
+ keystring += 2;
+ }
+ else if (*keystring == ';')
+ {
+ outsep2 = US"";
+ keystring++;
+ }
+ Uskip_whitespace(&keystring);
}
-/* Check for a defer behaviour keyword. */
+/* Check for a modifier keyword. */
-if (strncmpic(keystring, US"defer_", 6) == 0)
+for (;;)
{
- keystring += 6;
- if (strncmpic(keystring, US"strict", 6) == 0)
+ if (strncmpic(keystring, US"defer_", 6) == 0)
{
- defer_mode = DEFER;
keystring += 6;
+ if (strncmpic(keystring, US"strict", 6) == 0)
+ { defer_mode = DEFER; keystring += 6; }
+ else if (strncmpic(keystring, US"lax", 3) == 0)
+ { defer_mode = PASS; keystring += 3; }
+ else if (strncmpic(keystring, US"never", 5) == 0)
+ { defer_mode = OK; keystring += 5; }
+ else
+ {
+ *errmsg = US"unsupported dnsdb defer behaviour";
+ rc = DEFER;
+ goto out;
+ }
}
- else if (strncmpic(keystring, US"lax", 3) == 0)
+ else if (strncmpic(keystring, US"dnssec_", 7) == 0)
{
- defer_mode = PASS;
- keystring += 3;
+ keystring += 7;
+ if (strncmpic(keystring, US"strict", 6) == 0)
+ { dnssec_mode = DEFER; keystring += 6; }
+ else if (strncmpic(keystring, US"lax", 3) == 0)
+ { dnssec_mode = PASS; keystring += 3; }
+ else if (strncmpic(keystring, US"never", 5) == 0)
+ { dnssec_mode = OK; keystring += 5; }
+ else
+ {
+ *errmsg = US"unsupported dnsdb dnssec behaviour";
+ rc = DEFER;
+ goto out;
+ }
}
- else if (strncmpic(keystring, US"never", 5) == 0)
+ else if (strncmpic(keystring, US"retrans_", 8) == 0)
{
- defer_mode = OK;
- keystring += 5;
+ int timeout_sec;
+ if ((timeout_sec = readconf_readtime(keystring += 8, ',', FALSE)) <= 0)
+ {
+ *errmsg = US"unsupported dnsdb timeout value";
+ rc = DEFER;
+ goto out;
+ }
+ dns_retrans = timeout_sec;
+ while (*keystring != ',') keystring++;
}
- else
+ else if (strncmpic(keystring, US"retry_", 6) == 0)
{
- *errmsg = US"unsupported dnsdb defer behaviour";
- return DEFER;
+ int retries;
+ if ((retries = (int)strtol(CCS keystring + 6, CSS &keystring, 0)) < 0)
+ {
+ *errmsg = US"unsupported dnsdb retry count";
+ rc = DEFER;
+ goto out;
+ }
+ dns_retry = retries;
}
- while (isspace(*keystring)) keystring++;
+ else
+ break;
+
+ Uskip_whitespace(&keystring);
if (*keystring++ != ',')
{
- *errmsg = US"dnsdb defer behaviour syntax error";
- return DEFER;
+ *errmsg = US"dnsdb modifier syntax error";
+ rc = DEFER;
+ goto out;
}
- while (isspace(*keystring)) keystring++;
+ Uskip_whitespace(&keystring);
}
-/* If the keystring contains an = this must be preceded by a valid type name. */
+/* Figure out the "type" value if it is not T_TXT.
+If the keystring contains an = this must be preceded by a valid type name. */
+type = T_TXT;
if ((equals = Ustrchr(keystring, '=')) != NULL)
{
int i, len;
while (tend > keystring && isspace(tend[-1])) tend--;
len = tend - keystring;
- for (i = 0; i < sizeof(type_names)/sizeof(uschar *); i++)
- {
+ for (i = 0; i < nelem(type_names); i++)
if (len == Ustrlen(type_names[i]) &&
strncmpic(keystring, US type_names[i], len) == 0)
{
type = type_values[i];
break;
}
- }
- if (i >= sizeof(type_names)/sizeof(uschar *))
+ if (i >= nelem(type_names))
{
*errmsg = US"unsupported DNS record type";
- return DEFER;
+ rc = DEFER;
+ goto out;
}
keystring = equals + 1;
- while (isspace(*keystring)) keystring++;
+ Uskip_whitespace(&keystring);
}
/* Initialize the resolver in case this is the first time it has been used. */
-dns_init(FALSE, FALSE);
+dns_init(FALSE, FALSE, dnssec_mode != OK);
/* The remainder of the string must be a list of domains. As long as the lookup
for at least one of them succeeds, we return success. Failure means that none
it is treated as one item. */
if (type == T_PTR && keystring[0] != '<' &&
- string_is_ip_address(keystring, NULL) > 0)
+ string_is_ip_address(keystring, NULL) != 0)
sep = -1;
+/* SPF strings should be concatenated without a separator, thus make
+it the default if not defined (see RFC 4408 section 3.1.3).
+Multiple SPF records are forbidden (section 3.1.2) but are currently
+not handled specially, thus they are concatenated with \n by default.
+MX priority and value are space-separated by default.
+SRV and TLSA record parts are space-separated by default. */
+
+if (!outsep2) switch(type)
+ {
+ case T_SPF: outsep2 = US""; break;
+ case T_SRV: case T_MX: case T_TLSA: outsep2 = US" "; break;
+ }
+
/* Now scan the list and do a lookup for each item */
-while ((domain = string_nextinlist(&keystring, &sep, buffer, sizeof(buffer)))
- != NULL)
+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
doing the reversal is now in a separate function. */
if ((type == T_PTR || type == T_CSA) &&
- string_is_ip_address(domain, NULL) > 0)
- {
- dns_build_reverse(domain, rbuffer);
- domain = rbuffer;
- }
-
- DEBUG(D_lookup) debug_printf("dnsdb key: %s\n", domain);
+ string_is_ip_address(domain, NULL) != 0)
+ domain = dns_build_reverse(domain);
- /* Do the lookup and sort out the result. There are two special types that
- are handled specially: T_ZNS and T_MXH. The former is handled in a special
- lookup function so that the facility could be used from other parts of the
- Exim code. The latter affects only what happens later on in this function,
- but for tidiness it is handled in a similar way. If the lookup fails,
- continue with the next domain. In the case of DEFER, adjust the final
- "nothing found" result, but carry on to the next domain. */
-
- found = domain;
- rc = dns_special_lookup(&dnsa, domain, type, &found);
-
- if (rc == DNS_NOMATCH || rc == DNS_NODATA) continue;
- if (rc != DNS_SUCCEED)
+ do
{
- if (defer_mode == DEFER) return DEFER; /* always defer */
- else 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 != NULL;
- rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
- {
- if (rr->type != searchtype) continue;
+ 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.
+ The first two are handled in a special lookup function so that the facility
+ could be used from other parts of the Exim code. T_ADDRESSES is handled by looping
+ over the types of A lookup. T_MXH affects only what happens later on in
+ this function, but for tidiness it is handled by the "special". If the
+ lookup fails, continue with the next domain. In the case of DEFER, adjust
+ the final "nothing found" result, but carry on to the next domain. */
+
+ found = domain;
+#if HAVE_IPV6
+ if (type == T_ADDRESSES) /* NB cannot happen unless HAVE_IPV6 */
+ {
+ if (searchtype == T_ADDRESSES) searchtype = T_AAAA;
+ else if (searchtype == T_AAAA) searchtype = T_A;
+ rc = dns_special_lookup(dnsa, domain, searchtype, CUSS &found);
+ }
+ else
+#endif
+ rc = dns_special_lookup(dnsa, domain, type, CUSS &found);
- /* There may be several addresses from an A6 record. Put the configured
- separator between them, just as for between several records. However, A6
- support is not normally configured these days. */
+ lookup_dnssec_authenticated = dnssec_mode==OK ? NULL
+ : dns_is_secure(dnsa) ? US"yes" : US"no";
- if (type == T_A ||
- #ifdef SUPPORT_A6
- type == T_A6 ||
- #endif
- type == T_AAAA)
+ if (rc == DNS_NOMATCH || rc == DNS_NODATA) continue;
+ if ( rc != DNS_SUCCEED
+ || (dnssec_mode == DEFER && !dns_is_secure(dnsa))
+ )
{
- dns_address *da;
- for (da = dns_address_from_rr(&dnsa, rr); da != NULL; da = da->next)
- {
- if (ptr != 0) yield = string_cat(yield, &size, &ptr, outsep, 1);
- yield = string_cat(yield, &size, &ptr, da->address,
- Ustrlen(da->address));
- }
- continue;
+ if (defer_mode == DEFER)
+ {
+ dns_retrans = save_retrans;
+ dns_retry = save_retry;
+ dns_init(FALSE, FALSE, FALSE); /* clr dnssec bit */
+ rc = DEFER; /* always defer */
+ goto out;
+ }
+ if (defer_mode == PASS) failrc = DEFER; /* defer only if all do */
+ continue; /* treat defer as fail */
}
- /* Other kinds of record just have one piece of data each, but there may be
- several of them, of course. */
- if (ptr != 0) yield = string_cat(yield, &size, &ptr, outsep, 1);
+ /* Search the returned records */
- if (type == T_TXT)
- {
- yield = string_cat(yield, &size, &ptr, (uschar *)(rr->data+1),
- (rr->data)[0]);
- }
- else /* T_CNAME, T_CSA, T_MX, T_MXH, T_NS, T_PTR, T_SRV */
+ for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == searchtype)
{
- int priority, weight, port;
- uschar s[264];
- uschar *p = (uschar *)(rr->data);
+ if (*do_cache > rr->ttl)
+ *do_cache = rr->ttl;
- if (type == T_MXH)
- {
- /* mxh ignores the priority number and includes only the hostnames */
- GETSHORT(priority, p);
- }
- else if (type == T_MX)
+ if (type == T_A || type == T_AAAA || type == T_ADDRESSES)
{
- GETSHORT(priority, p);
- sprintf(CS s, "%d ", priority);
- yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
+ for (dns_address * da = dns_address_from_rr(dnsa, rr); da; da = da->next)
+ yield = string_append_listele(yield, *outsep, da->address);
+ continue;
}
- else if (type == T_SRV)
+
+ /* Other kinds of record just have one piece of data each, but there may be
+ several of them, of course. TXT & SPF can have data in multiple chunks. */
+
+ if (yield->ptr) yield = string_catn(yield, outsep, 1);
+
+ if (type == T_TXT || type == T_SPF)
+ for (unsigned data_offset = 0; data_offset + 1 < rr->size; )
+ {
+ uschar chunk_len = (rr->data)[data_offset];
+ int remain;
+
+ if (outsep2 && *outsep2 && data_offset != 0)
+ yield = string_catn(yield, outsep2, 1);
+
+ /* Apparently there are resolvers that do not check RRs before passing
+ them on, and glibc fails to do so. So every application must...
+ Check for chunk len exceeding RR */
+
+ remain = rr->size - ++data_offset;
+ if (chunk_len > remain)
+ chunk_len = remain;
+ yield = string_catn(yield, US ((rr->data) + data_offset), chunk_len);
+ data_offset += chunk_len;
+
+ if (!outsep2) break; /* output only the first chunk of the RR */
+ }
+ else if (type == T_TLSA)
+ if (rr->size < 3)
+ continue;
+ else
+ {
+ uint8_t usage, selector, matching_type;
+ uint16_t payload_length;
+ uschar s[MAX_TLSA_EXPANDED_SIZE];
+ uschar * sp = s;
+ uschar * p = US rr->data;
+
+ usage = *p++;
+ selector = *p++;
+ matching_type = *p++;
+ /* What's left after removing the first 3 bytes above */
+ payload_length = rr->size - 3;
+ sp += sprintf(CS s, "%d%c%d%c%d%c", usage, *outsep2,
+ selector, *outsep2, matching_type, *outsep2);
+ /* Now append the cert/identifier, one hex char at a time */
+ while (payload_length-- > 0 && sp-s < (MAX_TLSA_EXPANDED_SIZE - 4))
+ sp += sprintf(CS sp, "%02x", *p++);
+
+ yield = string_cat(yield, s);
+ }
+ else /* T_CNAME, T_CSA, T_MX, T_MXH, T_NS, T_PTR, T_SOA, T_SRV */
{
- GETSHORT(priority, p);
- GETSHORT(weight, p);
- GETSHORT(port, p);
- sprintf(CS s, "%d %d %d ", priority, weight, port);
- yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
+ int priority, weight, port;
+ uschar s[264];
+ uschar * p = US rr->data;
+
+ switch (type)
+ {
+ case T_MXH:
+ if (rr_bad_size(rr, sizeof(uint16_t))) continue;
+ /* mxh ignores the priority number and includes only the hostnames */
+ GETSHORT(priority, p);
+ break;
+
+ case T_MX:
+ if (rr_bad_size(rr, sizeof(uint16_t))) continue;
+ GETSHORT(priority, p);
+ sprintf(CS s, "%d%c", priority, *outsep2);
+ yield = string_cat(yield, s);
+ break;
+
+ case T_SRV:
+ if (rr_bad_size(rr, 3*sizeof(uint16_t))) continue;
+ GETSHORT(priority, p);
+ GETSHORT(weight, p);
+ GETSHORT(port, p);
+ sprintf(CS s, "%d%c%d%c%d%c", priority, *outsep2,
+ weight, *outsep2, port, *outsep2);
+ yield = string_cat(yield, s);
+ break;
+
+ case T_CSA:
+ if (rr_bad_size(rr, 3*sizeof(uint16_t))) continue;
+ /* See acl_verify_csa() for more comments about CSA. */
+ GETSHORT(priority, p);
+ GETSHORT(weight, p);
+ GETSHORT(port, p);
+
+ if (priority != 1) continue; /* CSA version must be 1 */
+
+ /* If the CSA record we found is not the one we asked for, analyse
+ the subdomain assertions in the port field, else analyse the direct
+ authorization status in the weight field. */
+
+ if (Ustrcmp(found, domain) != 0)
+ {
+ if (port & 1) *s = 'X'; /* explicit authorization required */
+ else *s = '?'; /* no subdomain assertions here */
+ }
+ else
+ {
+ if (weight < 2) *s = 'N'; /* not authorized */
+ else if (weight == 2) *s = 'Y'; /* authorized */
+ else if (weight == 3) *s = '?'; /* unauthorizable */
+ else continue; /* invalid */
+ }
+
+ s[1] = ' ';
+ yield = string_catn(yield, s, 2);
+ break;
+
+ default:
+ break;
+ }
+
+ /* GETSHORT() has advanced the pointer to the target domain. */
+
+ 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
+ truncated and dn_expand may fail. */
+
+ if (rc < 0)
+ {
+ log_write(0, LOG_MAIN, "host name alias list truncated: type=%s "
+ "domain=%s", dns_text_type(type), domain);
+ break;
+ }
+ else yield = string_cat(yield, s);
+
+ if (type == T_SOA && outsep2 != NULL)
+ {
+ unsigned long serial = 0, refresh = 0, retry = 0, expire = 0, minimum = 0;
+
+ p += rc;
+ yield = string_catn(yield, outsep2, 1);
+
+ rc = dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen, p,
+ (DN_EXPAND_ARG4_TYPE)s, sizeof(s));
+ if (rc < 0)
+ {
+ log_write(0, LOG_MAIN, "responsible-mailbox truncated: type=%s "
+ "domain=%s", dns_text_type(type), domain);
+ break;
+ }
+ else yield = string_cat(yield, s);
+
+ p += rc;
+ if (!rr_bad_increment(rr, p, 5 * sizeof(u_int32_t)))
+ {
+ GETLONG(serial, p); GETLONG(refresh, p);
+ GETLONG(retry, p); GETLONG(expire, p); GETLONG(minimum, p);
+ }
+ sprintf(CS s, "%c%lu%c%lu%c%lu%c%lu%c%lu",
+ *outsep2, serial, *outsep2, refresh,
+ *outsep2, retry, *outsep2, expire, *outsep2, minimum);
+ yield = string_cat(yield, s);
+ }
}
- else if (type == T_CSA)
- {
- /* See acl_verify_csa() for more comments about CSA. */
+ } /* Loop for list of returned records */
- GETSHORT(priority, p);
- GETSHORT(weight, p);
- GETSHORT(port, p);
+ /* Loop for set of A-lookup types */
+ } while (type == T_ADDRESSES && searchtype != T_A);
- if (priority != 1) continue; /* CSA version must be 1 */
+ } /* Loop for list of domains */
- /* If the CSA record we found is not the one we asked for, analyse
- the subdomain assertions in the port field, else analyse the direct
- authorization status in the weight field. */
+/* Reclaim unused memory */
- if (found != domain)
- {
- if (port & 1) *s = 'X'; /* explicit authorization required */
- else *s = '?'; /* no subdomain assertions here */
- }
- else
- {
- if (weight < 2) *s = 'N'; /* not authorized */
- else if (weight == 2) *s = 'Y'; /* authorized */
- else if (weight == 3) *s = '?'; /* unauthorizable */
- else continue; /* invalid */
- }
+gstring_release_unused(yield);
- s[1] = ' ';
- yield = string_cat(yield, &size, &ptr, s, 2);
- }
+/* If yield NULL we have not found anything. Otherwise, insert the terminating
+zero and return the result. */
- /* GETSHORT() has advanced the pointer to the target domain. */
+dns_retrans = save_retrans;
+dns_retry = save_retry;
+dns_init(FALSE, FALSE, FALSE); /* clear the dnssec bit for getaddrbyname */
- rc = dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p,
- (DN_EXPAND_ARG4_TYPE)(s), sizeof(s));
+if (!yield || !yield->ptr)
+ rc = failrc;
+else
+ {
+ *result = string_from_gstring(yield);
+ rc = OK;
+ }
- /* If an overlong response was received, the data will have been
- truncated and dn_expand may fail. */
+out:
- if (rc < 0)
- {
- log_write(0, LOG_MAIN, "host name alias list truncated: type=%s "
- "domain=%s", dns_text_type(type), domain);
- break;
- }
- else yield = string_cat(yield, &size, &ptr, s, Ustrlen(s));
- }
- } /* Loop for list of returned records */
- } /* Loop for list of domains */
+store_free_dns_answer(dnsa);
+return rc;
+}
-/* Reclaim unused memory */
-store_reset(yield + ptr + 1);
-/* If ptr == 0 we have not found anything. Otherwise, insert the terminating
-zero and return the result. */
+/*************************************************
+* Version reporting entry point *
+*************************************************/
-if (ptr == 0) return failrc;
-yield[ptr] = 0;
-*result = yield;
-return OK;
+/* See local README for interface description. */
+
+#include "../version.h"
+
+gstring *
+dnsdb_version_report(gstring * g)
+{
+#ifdef DYNLOOKUP
+g = string_fmt_append(g, "Library version: DNSDB: Exim version %s\n", EXIM_VERSION_STR);
+#endif
+return g;
}
+
+static lookup_info _lookup_info = {
+ .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
+#define dnsdb_lookup_module_info _lookup_module_info
+#endif
+
+static lookup_info *_lookup_list[] = { &_lookup_info };
+lookup_module_info dnsdb_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 };
+
+/* vi: aw ai sw=2
+*/
/* End of lookups/dnsdb.c */
git://git.exim.org / exim.git / blobdiff