rwrap: Add support to handle NS records

Signed-off-by: Richard Sharpe <rsharpe@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Jakub Hrozek <jakub.hrozek@posteo.se>

1 files changed, 60 insertions, 1 deletions

diff --git a/src/resolv_wrapper.c b/src/resolv_wrapper.c
index 72005fa..48018be 100644
--- a/src/resolv_wrapper.c
+++ b/src/resolv_wrapper.c
@@ -231,6 +231,15 @@ static int rwrap_create_fake_aaaa_rr(const char *key,
 	rr->type = ns_t_aaaa;
 	return 0;
 }
+static int rwrap_create_fake_ns_rr(const char *key,
+				   const char *value,
+				   struct rwrap_fake_rr *rr)
+{
+	memcpy(rr->rrdata.srv_rec.hostname, value, strlen(value) + 1);
+	memcpy(rr->key, key, strlen(key) + 1);
+	rr->type = ns_t_ns;
+	return 0;
+}
 
 static int rwrap_create_fake_srv_rr(const char *key,
 				    const char *value,
@@ -473,6 +482,47 @@ static ssize_t rwrap_fake_aaaa(struct rwrap_fake_rr *rr,
 	return resp_size;
 }
 
+static ssize_t rwrap_fake_ns(struct rwrap_fake_rr *rr,
+			     uint8_t *answer,
+			    size_t anslen)
+{
+	uint8_t *a = answer;
+	ssize_t resp_size = 0;
+	size_t rdata_size;
+	unsigned char hostname_compressed[MAXDNAME];
+	ssize_t compressed_len;
+
+	if (rr == NULL || rr->type != ns_t_ns) {
+		RWRAP_LOG(RWRAP_LOG_ERROR,
+			  "Malformed record, no or wrong value!\n");
+		return -1;
+	}
+	RWRAP_LOG(RWRAP_LOG_TRACE, "Adding NS RR");
+
+	/* Prepare the data to write */
+	compressed_len = ns_name_compress(rr->rrdata.srv_rec.hostname,
+					  hostname_compressed,
+					  MAXDNAME,
+					  NULL,
+					  NULL);
+	if (compressed_len < 0) {
+		return -1;
+	}
+
+	/* Is this enough? */
+	rdata_size = compressed_len;
+
+	resp_size = rwrap_fake_rdata_common(ns_t_ns, rdata_size,
+					    rr->key, anslen, &a);
+	if (resp_size < 0) {
+		return -1;
+	}
+
+	memcpy(a, hostname_compressed, compressed_len);
+
+	return resp_size;
+}
+
 static ssize_t rwrap_fake_srv(struct rwrap_fake_rr *rr,
 			      uint8_t *answer,
 			      size_t anslen)
@@ -666,7 +716,8 @@ static int rwrap_get_record(const char *hostfile, unsigned recursion,
 	}
 
 	RWRAP_LOG(RWRAP_LOG_TRACE,
-		  "Searching in fake hosts file %s\n", hostfile);
+		  "Searching in fake hosts file %s for %s:%d\n", hostfile,
+		  query, type);
 
 	fp = fopen(hostfile, "r");
 	if (fp == NULL) {
@@ -706,6 +757,10 @@ static int rwrap_get_record(const char *hostfile, unsigned recursion,
 				      rec_type, "AAAA", key, query)) {
 			rc = rwrap_create_fake_aaaa_rr(key, value, rr);
 			break;
+		} else if (TYPE_MATCH(type, ns_t_ns,
+				      rec_type, "NS", key, query)) {
+			rc = rwrap_create_fake_ns_rr(key, value, rr);
+			break;
 		} else if (TYPE_MATCH(type, ns_t_srv,
 				      rec_type, "SRV", key, query)) {
 			rc = rwrap_create_fake_srv_rr(key, value, rr);
@@ -780,6 +835,7 @@ static inline bool rwrap_known_type(int type)
 	switch (type) {
 	case ns_t_a:
 	case ns_t_aaaa:
+	case ns_t_ns:
 	case ns_t_srv:
 	case ns_t_soa:
 	case ns_t_cname:
@@ -839,6 +895,9 @@ static ssize_t rwrap_add_rr(struct rwrap_fake_rr *rr,
 	case ns_t_aaaa:
 		resp_data = rwrap_fake_aaaa(rr, answer, anslen);
 		break;
+	case ns_t_ns:
+		resp_data = rwrap_fake_ns(rr, answer, anslen);
+		break;
 	case ns_t_srv:
 		resp_data = rwrap_fake_srv(rr, answer, anslen);
 		break;