#include "exim.h"
-/* Function declaration needed for mutual recursion when A6 records
-are supported. */
-
-#if HAVE_IPV6
-#ifdef SUPPORT_A6
-static void dns_complete_a6(dns_address ***, dns_answer *, dns_record *,
- int, uschar *);
-#endif
-#endif
-
/*************************************************
* Fake DNS resolver *
*/
void
-dns_build_reverse(uschar *string, uschar *buffer)
+dns_build_reverse(const uschar *string, uschar *buffer)
{
-uschar *p = string + Ustrlen(string);
+const uschar *p = string + Ustrlen(string);
uschar *pp = buffer;
/* Handle IPv4 address */
int i;
for (i = 0; i < 4; i++)
{
- uschar *ppp = p;
+ const uschar *ppp = p;
while (ppp > string && ppp[-1] != '.') ppp--;
Ustrncpy(pp, ppp, p - ppp);
pp += p - ppp;
{
#ifndef STAND_ALONE
int rc = -1;
-uschar *save;
+const uschar *save_domain;
#endif
res_state resp = os_get_dns_resolver_res();
return previous->data.val;
}
+#ifdef EXPERIMENTAL_INTERNATIONAL
+/* Convert all names to a-label form before doing lookup */
+ {
+ uschar * alabel;
+ uschar * errstr = NULL;
+ DEBUG(D_dns) if (string_is_utf8(name))
+ debug_printf("convert utf8 '%s' to alabel for for lookup\n", name);
+ if ((alabel = string_domain_utf8_to_alabel(name, &errstr)), errstr)
+ {
+ DEBUG(D_dns)
+ debug_printf("DNS name '%s' utf8 conversion to alabel failed: %s\n", name,
+ errstr);
+ host_find_failed_syntax = TRUE;
+ return DNS_NOMATCH;
+ }
+ name = alabel;
+ }
+#endif
+
/* If configured, check the hygene of the name passed to lookup. Otherwise,
although DNS lookups may give REFUSED at the lower level, some resolvers
turn this into TRY_AGAIN, which is silly. Give a NOMATCH return, since such
nameservers are also believed to do this. It is, of course, contrary to the
specification of the DNS, so we lock it out. */
-if ((
- #ifdef SUPPORT_A6
- type == T_A6 ||
- #endif
- type == T_A || type == T_AAAA) &&
- string_is_ip_address(name, NULL) != 0)
+if ((type == T_A || type == T_AAAA) && string_is_ip_address(name, NULL) != 0)
return DNS_NOMATCH;
/* If we are running in the test harness, instead of calling the normal resolver
(res_search), we call fakens_search(), which recognizes certain special
domains, and interfaces to a fake nameserver for certain special zones. */
-if (running_in_test_harness)
- dnsa->answerlen = fakens_search(name, type, dnsa->answer, MAXPACKET);
-else
- dnsa->answerlen = res_search(CCS name, C_IN, type, dnsa->answer, MAXPACKET);
+dnsa->answerlen = running_in_test_harness
+ ? fakens_search(name, type, dnsa->answer, MAXPACKET)
+ : res_search(CCS name, C_IN, type, dnsa->answer, MAXPACKET);
if (dnsa->answerlen > MAXPACKET)
{
/* Cut this out for various test programs */
#ifndef STAND_ALONE
- save = deliver_domain;
+ save_domain = deliver_domain;
deliver_domain = string_copy(name); /* set $domain */
- rc = match_isinlist(name, &dns_again_means_nonexist, 0, NULL, NULL,
+ rc = match_isinlist(name, (const uschar **)&dns_again_means_nonexist, 0, NULL, NULL,
MCL_DOMAIN, TRUE, NULL);
- deliver_domain = save;
+ deliver_domain = save_domain;
if (rc != OK)
{
DEBUG(D_dns) debug_printf("returning DNS_AGAIN\n");
If fully_qualified_name is not NULL, set it to point to the full name
returned by the resolver, if this is different to what it is given, unless
the returned name starts with "*" as some nameservers seem to be returning
-wildcards in this form.
+wildcards in this form. In international mode "different" means "alabel
+forms are different".
Arguments:
dnsa pointer to dns_answer structure
int
dns_lookup(dns_answer *dnsa, const uschar *name, int type,
- uschar **fully_qualified_name)
+ const uschar **fully_qualified_name)
{
int i;
const uschar *orig_name = name;
if (i == 0 && fully_qualified_name != NULL)
{
- if (cname_rr.data != NULL)
- {
- if (Ustrcmp(cname_rr.name, *fully_qualified_name) != 0 &&
- cname_rr.name[0] != '*')
- *fully_qualified_name = string_copy_dnsdomain(cname_rr.name);
- }
- else if (type_rr.data != NULL)
- {
- if (Ustrcmp(type_rr.name, *fully_qualified_name) != 0 &&
- type_rr.name[0] != '*')
- *fully_qualified_name = string_copy_dnsdomain(type_rr.name);
- }
+ uschar * rr_name = cname_rr.data ? cname_rr.name
+ : type_rr.data ? type_rr.name : NULL;
+ if ( rr_name
+ && Ustrcmp(rr_name, *fully_qualified_name) != 0
+ && rr_name[0] != '*'
+#ifdef EXPERIMENTAL_INTERNATIONAL
+ && ( !string_is_utf8(*fully_qualified_name)
+ || Ustrcmp(rr_name,
+ string_domain_utf8_to_alabel(*fully_qualified_name, NULL)) != 0
+ )
+#endif
+ )
+ *fully_qualified_name = string_copy_dnsdomain(rr_name);
}
/* If any data records of the correct type were found, we are done. */
int
dns_special_lookup(dns_answer *dnsa, const uschar *name, int type,
- uschar **fully_qualified_name)
+ const uschar **fully_qualified_name)
{
if (type >= 0) return dns_lookup(dnsa, name, type, fully_qualified_name);
-/* Support for A6 records has been commented out since they were demoted to
-experimental status at IETF 51. */
-
-#if HAVE_IPV6 && defined(SUPPORT_A6)
-
-/*************************************************
-* Search DNS block for prefix RRs *
-*************************************************/
-
-/* Called from dns_complete_a6() to search an additional section or a main
-answer section for required prefix records to complete an IPv6 address obtained
-from an A6 record. For each prefix record, a recursive call to dns_complete_a6
-is made, with a new copy of the address so far.
-
-Arguments:
- dnsa the DNS answer block
- which RESET_ADDITIONAL or RESET_ANSWERS
- name name of prefix record
- yptrptr pointer to the pointer that points to where to hang the next
- dns_address structure
- bits number of bits we have already got
- bitvec the bits we have already got
-
-Returns: TRUE if any records were found
-*/
-
-static BOOL
-dns_find_prefix(dns_answer *dnsa, int which, uschar *name, dns_address
- ***yptrptr, int bits, uschar *bitvec)
-{
-BOOL yield = FALSE;
-dns_record *rr;
-dns_scan dnss;
-
-for (rr = dns_next_rr(dnsa, &dnss, which);
- rr != NULL;
- rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
- {
- uschar cbitvec[16];
- if (rr->type != T_A6 || strcmpic(rr->name, name) != 0) continue;
- yield = TRUE;
- memcpy(cbitvec, bitvec, sizeof(cbitvec));
- dns_complete_a6(yptrptr, dnsa, rr, bits, cbitvec);
- }
-
-return yield;
-}
-
-
-
-/*************************************************
-* Follow chains of A6 records *
-*************************************************/
-
-/* A6 records may be incomplete, with pointers to other records containing more
-bits of the address. There can be a tree structure, leading to a number of
-addresses originating from a single initial A6 record.
-
-Arguments:
- yptrptr pointer to the pointer that points to where to hang the next
- dns_address structure
- dnsa the current DNS answer block
- rr the RR we have at present
- bits number of bits we have already got
- bitvec the bits we have already got
-
-Returns: nothing
-*/
-
-static void
-dns_complete_a6(dns_address ***yptrptr, dns_answer *dnsa, dns_record *rr,
- int bits, uschar *bitvec)
-{
-static uschar bitmask[] = { 0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80 };
-uschar *p = (uschar *)(rr->data);
-int prefix_len, suffix_len;
-int i, j, k;
-uschar *chainptr;
-uschar chain[264];
-dns_answer cdnsa;
-
-/* The prefix length is the first byte. It defines the prefix which is missing
-from the data in this record as a number of bits. Zero means this is the end of
-a chain. The suffix is the data in this record; only sufficient bytes to hold
-it are supplied. There may be zero bytes. We have to ignore trailing bits that
-we have already obtained from earlier RRs in the chain. */
-
-prefix_len = *p++; /* bits */
-suffix_len = (128 - prefix_len + 7)/8; /* bytes */
-
-/* If the prefix in this record is greater than the prefix in the previous
-record in the chain, we have to ignore the record (RFC 2874). */
-
-if (prefix_len > 128 - bits) return;
-
-/* In this little loop, the number of bits up to and including the current byte
-is held in k. If we have none of the bits in this byte, we can just or it into
-the current data. If we have all of the bits in this byte, we skip it.
-Otherwise, some masking has to be done. */
-
-for (i = suffix_len - 1, j = 15, k = 8; i >= 0; i--)
- {
- int required = k - bits;
- if (required >= 8) bitvec[j] |= p[i];
- else if (required > 0) bitvec[j] |= p[i] & bitmask[required];
- j--; /* I tried putting these in the "for" statement, but gcc muttered */
- k += 8; /* about computed values not being used. */
- }
-
-/* If the prefix_length is zero, we are at the end of a chain. Build a
-dns_address item with the current data, hang it onto the end of the chain,
-adjust the hanging pointer, and we are done. */
-
-if (prefix_len == 0)
- {
- dns_address *new = store_get(sizeof(dns_address) + 50);
- inet_ntop(AF_INET6, bitvec, CS new->address, 50);
- new->next = NULL;
- **yptrptr = new;
- *yptrptr = &(new->next);
- return;
- }
-
-/* Prefix length is not zero. Reset the number of bits that we have collected
-so far, and extract the chain name. */
-
-bits = 128 - prefix_len;
-p += suffix_len;
-
-chainptr = chain;
-while ((i = *p++) != 0)
- {
- if (chainptr != chain) *chainptr++ = '.';
- memcpy(chainptr, p, i);
- chainptr += i;
- p += i;
- }
-*chainptr = 0;
-chainptr = chain;
-
-/* Now scan the current DNS response record to see if the additional section
-contains the records we want. This processing can be cut out for testing
-purposes. */
-
-if (dns_find_prefix(dnsa, RESET_ADDITIONAL, chainptr, yptrptr, bits, bitvec))
- return;
-
-/* No chain records were found in the current DNS response block. Do a new DNS
-lookup to try to find these records. This opens up the possibility of DNS
-failures. We ignore them at this point; if all branches of the tree fail, there
-will be no addresses at the end. */
-
-if (dns_lookup(&cdnsa, chainptr, T_A6, NULL) == DNS_SUCCEED)
- (void)dns_find_prefix(&cdnsa, RESET_ANSWERS, chainptr, yptrptr, bits, bitvec);
-}
-#endif /* HAVE_IPV6 && defined(SUPPORT_A6) */
-
-
/*************************************************
{
dns_address *yield = NULL;
-#if HAVE_IPV6 && defined(SUPPORT_A6)
-dns_address **yieldptr = &yield;
-uschar bitvec[16];
-#else
dnsa = dnsa; /* Stop picky compilers warning */
-#endif
if (rr->type == T_A)
{
#if HAVE_IPV6
-#ifdef SUPPORT_A6
-else if (rr->type == T_A6)
- {
- memset(bitvec, 0, sizeof(bitvec));
- dns_complete_a6(&yieldptr, dnsa, rr, 0, bitvec);
- }
-#endif /* SUPPORT_A6 */
-
else
{
yield = store_get(sizeof(dns_address) + 50);
git://git.exim.org / exim.git / blobdiff