From 79ddedabf80d5c4dc42eb7a527545796f7d1e330 Mon Sep 17 00:00:00 2001
From: Evan Hunt <each@isc.org>
Date: Tue, 2 Nov 2021 23:06:10 -0700
Subject: [PATCH] test ECS information is passed in dlzexternal

the dlzexternal test driver now includes ECS, if present in the
query, in the TXT record returned for QNAME "source-addr".
---
 bin/tests/system/dlzexternal/driver/driver.c | 12 ++++++++++++
 bin/tests/system/dlzexternal/tests.sh        |  8 ++++++++
 contrib/dlz/example/dlz_example.c            |  7 ++++---
 contrib/dlz/modules/include/dlz_minimal.h    |  4 ++++
 4 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/bin/tests/system/dlzexternal/driver/driver.c b/bin/tests/system/dlzexternal/driver/driver.c
index a113208858..b8c74244e6 100644
--- a/bin/tests/system/dlzexternal/driver/driver.c
+++ b/bin/tests/system/dlzexternal/driver/driver.c
@@ -488,6 +488,7 @@ dlz_lookup(const char *zone, const char *name, void *dbdata,
 	}
 
 	if (strcmp(name, "source-addr") == 0) {
+		char ecsbuf[DNS_ECS_FORMATSIZE] = "not supported";
 		strncpy(buf, "unknown", sizeof(buf));
 		if (methods != NULL && methods->sourceip != NULL &&
 		    (methods->version - methods->age <=
@@ -497,6 +498,17 @@ dlz_lookup(const char *zone, const char *name, void *dbdata,
 			methods->sourceip(clientinfo, &src);
 			fmt_address(src, buf, sizeof(buf));
 		}
+		if (clientinfo != NULL && clientinfo->version >= 3) {
+			if (clientinfo->ecs.addr.family != AF_UNSPEC) {
+				dns_ecs_format(&clientinfo->ecs, ecsbuf,
+					       sizeof(ecsbuf));
+			} else {
+				snprintf(ecsbuf, sizeof(ecsbuf), "%s",
+					 "not present");
+			}
+		}
+		i = strlen(buf);
+		snprintf(buf + i, sizeof(buf) - i - 1, " ECS %s", ecsbuf);
 
 		loginfo("dlz_example: lookup connection from %s", buf);
 
diff --git a/bin/tests/system/dlzexternal/tests.sh b/bin/tests/system/dlzexternal/tests.sh
index 9ae428c232..08ab8a4f90 100644
--- a/bin/tests/system/dlzexternal/tests.sh
+++ b/bin/tests/system/dlzexternal/tests.sh
@@ -217,5 +217,13 @@ lookups=`grep "lookup #.*\.not\.there" ns1/named.run | wc -l`
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`
 
+newtest "checking ECS data is passed to driver in clientinfo"
+$DIG $DIGOPTS +short +subnet=192.0/16 source-addr.example.nil txt > dig.out.ns1.test$n.1 || ret=1
+grep "192.0.0.0/16/0" dig.out.ns1.test$n.1 > /dev/null || ret=1
+$DIG $DIGOPTS +short source-addr.example.nil txt > dig.out.ns1.test$n.2 || ret=1
+grep "not.*present" dig.out.ns1.test$n.2 > /dev/null || ret=1
+if [ $ret != 0 ]; then echo_i "failed"; fi
+status=`expr $status + $ret`
+
 echo_i "exit status: $status"
 [ $status -eq 0 ] || exit 1
diff --git a/contrib/dlz/example/dlz_example.c b/contrib/dlz/example/dlz_example.c
index daf9a40457..1ad12ce01a 100644
--- a/contrib/dlz/example/dlz_example.c
+++ b/contrib/dlz/example/dlz_example.c
@@ -438,8 +438,8 @@ dlz_lookup(const char *zone, const char *name, void *dbdata,
 	}
 
 	if (strcmp(name, "source-addr") == 0) {
-		char ecsbuf[100] = "not supported";
-		strcpy(buf, "unknown");
+		char ecsbuf[DNS_ECS_FORMATSIZE] = "not supported";
+		strncpy(buf, "unknown", sizeof(buf));
 		if (methods != NULL && methods->sourceip != NULL &&
 		    (methods->version - methods->age <=
 		     DNS_CLIENTINFOMETHODS_VERSION) &&
@@ -453,7 +453,8 @@ dlz_lookup(const char *zone, const char *name, void *dbdata,
 				dns_ecs_format(&clientinfo->ecs, ecsbuf,
 					       sizeof(ecsbuf));
 			} else {
-				strcpy(ecsbuf, "not present");
+				snprintf(ecsbuf, sizeof(ecsbuf), "%s",
+					 "not present");
 			}
 		}
 		i = strlen(buf);
diff --git a/contrib/dlz/modules/include/dlz_minimal.h b/contrib/dlz/modules/include/dlz_minimal.h
index a820527cd4..0225e7ad31 100644
--- a/contrib/dlz/modules/include/dlz_minimal.h
+++ b/contrib/dlz/modules/include/dlz_minimal.h
@@ -130,6 +130,10 @@ typedef struct dns_clientinfomethods {
 } dns_clientinfomethods_t;
 #endif /* DLZ_DLOPEN_VERSION > 1 */
 
+#define DNS_ECS_FORMATSIZE                                                \
+	sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:XXX.XXX.XXX.XXX%SSSSSSSSSS" \
+	       "/NNN/NNN")
+
 /*
  * Method definitions for callbacks provided by the dlopen driver
  */