Gitweb:
https://git.exim.org/exim.git/commitdiff/320fe6140189f08168dce2deca19821b4237e747
Commit: 320fe6140189f08168dce2deca19821b4237e747
Parent: 143b1159402424b930881bc8d25c640f1d6cd581
Author: Jeremy Harris <jgh146exb@???>
AuthorDate: Sat May 8 23:07:34 2021 +0100
Committer: Jeremy Harris <jgh146exb@???>
CommitDate: Sat May 8 23:07:34 2021 +0100
DNS: Better handling of SOA when negative-caching lookups
---
src/src/dns.c | 73 ++++++++++++++++++++++++--------------------------------
src/src/string.c | 2 +-
test/stderr/0277 | 4 ++++
test/stderr/0469 | 1 +
test/stderr/2202 | 2 ++
5 files changed, 39 insertions(+), 43 deletions(-)
diff --git a/src/src/dns.c b/src/src/dns.c
index 217fe5f..490eb88 100644
--- a/src/src/dns.c
+++ b/src/src/dns.c
@@ -730,37 +730,37 @@ dns_expire_from_soa(dns_answer * dnsa, int type)
{
dns_scan dnss;
-if (!fake_dnsa_len_for_fail(dnsa, type)) return 0;
+if (fake_dnsa_len_for_fail(dnsa, type))
+ for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_AUTHORITY);
+ rr; rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)
+ ) if (rr->type == T_SOA)
+ {
+ const uschar * p = rr->data;
+ uschar discard_buf[256];
+ int len;
+ unsigned long ttl;
+
+ /* Skip the mname & rname strings */
+
+ if ((len = dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen,
+ p, (DN_EXPAND_ARG4_TYPE)discard_buf, 256)) < 0)
+ break;
+ p += len;
+ if ((len = dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen,
+ p, (DN_EXPAND_ARG4_TYPE)discard_buf, 256)) < 0)
+ break;
+ p += len;
+
+ /* Skip the SOA serial, refresh, retry & expire. Grab the TTL */
+
+ if (p > dnsa->answer + dnsa->answerlen - 5 * INT32SZ)
+ break;
+ p += 4 * INT32SZ;
+ GETLONG(ttl, p);
+
+ return time(NULL) + ttl;
+ }
-for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_AUTHORITY);
- rr; rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)
- ) if (rr->type == T_SOA)
- {
- const uschar * p = rr->data;
- uschar discard_buf[256];
- int len;
- unsigned long ttl;
-
- /* Skip the mname & rname strings */
-
- if ((len = dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen,
- p, (DN_EXPAND_ARG4_TYPE)discard_buf, 256)) < 0)
- break;
- p += len;
- if ((len = dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen,
- p, (DN_EXPAND_ARG4_TYPE)discard_buf, 256)) < 0)
- break;
- p += len;
-
- /* Skip the SOA serial, refresh, retry & expire. Grab the TTL */
-
- if (p > dnsa->answer + dnsa->answerlen - 5 * INT32SZ)
- break;
- p += 4 * INT32SZ;
- GETLONG(ttl, p);
-
- return time(NULL) + ttl;
- }
DEBUG(D_dns) debug_printf("DNS: no SOA record found for neg-TTL\n");
return 0;
}
@@ -1205,18 +1205,7 @@ switch (type)
If the TLD and the 2LD exist but the explicit CSA record lookup failed, then
the AUTHORITY SOA will be the 2LD's or a subdomain thereof. */
- if (rc == DNS_NOMATCH)
- {
- if (!fake_dnsa_len_for_fail(dnsa, T_CSA)) return DNS_NOMATCH;
-
- for (rr = dns_next_rr(dnsa, &dnss, RESET_AUTHORITY);
- rr; rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)
- )
- if (rr->type != T_SOA) continue;
- else if (strcmpic(rr->name, US"") == 0 ||
- strcmpic(rr->name, tld) == 0) return DNS_NOMATCH;
- else break;
- }
+ if (rc == DNS_NOMATCH) return DNS_NOMATCH;
for (i = 0; i < limit; i++)
{
diff --git a/src/src/string.c b/src/src/string.c
index fbb1953..cb91324 100644
--- a/src/src/string.c
+++ b/src/src/string.c
@@ -960,7 +960,7 @@ else
&& (g->ptr == 1 || g->s[g->ptr-2] != '\\') )
g->ptr--;
buffer = string_from_gstring(g);
- gstring_release_unused_trc(g, func, line);
+ gstring_release_unused_trc(g, CCS func, line);
}
/* Update the current pointer and return the new string */
diff --git a/test/stderr/0277 b/test/stderr/0277
index 0cbd2a9..9f606b9 100644
--- a/test/stderr/0277
+++ b/test/stderr/0277
@@ -19,6 +19,7 @@ DNS lookup of 4.3.2.V4NET.in-addr.arpa (PTR) using fakens
DNS lookup of 4.3.2.V4NET.in-addr.arpa (PTR) gave HOST_NOT_FOUND
returning DNS_NOMATCH
DNS: couldn't fake dnsa len
+DNS: no SOA record found for neg-TTL
writing neg-cache entry for 4.3.2.V4NET.in-addr.arpa-PTR-xxxx, ttl -1
LOG: host_lookup_failed MAIN
no host name found for IP address V4NET.2.3.4
@@ -97,6 +98,7 @@ DNS lookup of 12.11.10.V4NET.in-addr.arpa (PTR) using fakens
DNS lookup of 12.11.10.V4NET.in-addr.arpa (PTR) gave HOST_NOT_FOUND
returning DNS_NOMATCH
DNS: couldn't fake dnsa len
+DNS: no SOA record found for neg-TTL
writing neg-cache entry for 12.11.10.V4NET.in-addr.arpa-PTR-xxxx, ttl -1
LOG: host_lookup_failed MAIN
no host name found for IP address V4NET.10.11.12
@@ -142,6 +144,7 @@ DNS lookup of 1.1.1.V4NET.in-addr.arpa (PTR) using fakens
DNS lookup of 1.1.1.V4NET.in-addr.arpa (PTR) gave HOST_NOT_FOUND
returning DNS_NOMATCH
DNS: couldn't fake dnsa len
+DNS: no SOA record found for neg-TTL
writing neg-cache entry for 1.1.1.V4NET.in-addr.arpa-PTR-xxxx, ttl -1
LOG: host_lookup_failed MAIN
no host name found for IP address V4NET.1.1.1
@@ -187,6 +190,7 @@ DNS lookup of 2.2.2.V4NET.in-addr.arpa (PTR) using fakens
DNS lookup of 2.2.2.V4NET.in-addr.arpa (PTR) gave HOST_NOT_FOUND
returning DNS_NOMATCH
DNS: couldn't fake dnsa len
+DNS: no SOA record found for neg-TTL
writing neg-cache entry for 2.2.2.V4NET.in-addr.arpa-PTR-xxxx, ttl -1
LOG: host_lookup_failed MAIN
no host name found for IP address V4NET.2.2.2
diff --git a/test/stderr/0469 b/test/stderr/0469
index f3b5593..4f6d216 100644
--- a/test/stderr/0469
+++ b/test/stderr/0469
@@ -25,6 +25,7 @@ DNS lookup of dontqualify (A) using fakens
DNS lookup of dontqualify (A) gave NO_DATA
returning DNS_NODATA
DNS: couldn't fake dnsa len
+DNS: no SOA record found for neg-TTL
writing neg-cache entry for dontqualify-A-xxxx, ttl -1
fully qualified name = mxt1c.test.ex
host_find_bydns yield = HOST_FIND_FAILED (0); returned hosts:
diff --git a/test/stderr/2202 b/test/stderr/2202
index a7c78ea..3ce1376 100644
--- a/test/stderr/2202
+++ b/test/stderr/2202
@@ -43,6 +43,7 @@ DNS lookup of cioce.test.again.dns (MX) gave TRY_AGAIN
cioce.test.again.dns in dns_again_means_nonexist? yes (matched "*")
cioce.test.again.dns is in dns_again_means_nonexist: returning DNS_NOMATCH
DNS: couldn't fake dnsa len
+DNS: no SOA record found for neg-TTL
writing neg-cache entry for cioce.test.again.dns-MX-xxxx, ttl -1
creating new cache entry
lookup failed
@@ -66,6 +67,7 @@ DNS lookup of cioce.test.again.dns (A) gave TRY_AGAIN
cioce.test.again.dns in dns_again_means_nonexist? yes (matched "*")
cioce.test.again.dns is in dns_again_means_nonexist: returning DNS_NOMATCH
DNS: couldn't fake dnsa len
+DNS: no SOA record found for neg-TTL
writing neg-cache entry for cioce.test.again.dns-A-xxxx, ttl -1
host_fake_gethostbyname(af=inet) returned 1 (HOST_NOT_FOUND)
no IP address found for host cioce.test.again.dns (during SMTP connection from the.local.host.name [ip4.ip4.ip4.ip4])
