Overload `local_data_remove` to support removing specific records (#1087)

Here we overload the `local_data_remove` control command to support
deleting specific records. Curently, this command deletes all records
for a given zone. The modification works by attempting to parse the
command argument first as a complete record and then as just a domain
name, if the first attempt failed.

This preserves the command's behavior, while also supporting removing
specific records from the zone tree.

Signed-off-by: R. Christian McDonald <rcm@rcm.sh>

diff --git a/daemon/remote.c b/daemon/remote.c
index 720f0daab4f1898a65f88f92d40e4a10df18d363..ccb6016bf5bb508d9a248ca9d0a467ce295e1a57 100644 (file)
--- a/daemon/remote.c
+++ b/daemon/remote.c
@@ -1,6 +1,7 @@
 /*
  * daemon/remote.c - remote control for the unbound daemon.
  *
+ * Copyright (c) 2024, Rubicon Communications, LLC ("Netgate"). All rights reserved.
  * Copyright (c) 2008, NLnet Labs. All rights reserved.
  *
  * This software is open source.
@@ -1533,18 +1534,95 @@ do_datas_add(struct daemon_remote* rc, RES* ssl, struct worker* worker)
        (void)ssl_printf(ssl, "added %d datas\n", num);
 }
 
+static int
+perform_data_remove_rr(RES* ssl, struct local_zones* local_zones,
+       uint8_t* rr, size_t len, size_t dname_len, char *arg)
+{
+       uint16_t rr_class, rr_type;
+       int labs, s;
+       struct local_zone* z;
+       struct local_data* ld;
+       uint8_t *rdata;
+       size_t rdata_len, index;
+       struct packed_rrset_data* d;
+
+       rdata = sldns_wirerr_get_rdatawl(rr, len, dname_len);
+       rdata_len = ((size_t)sldns_wirerr_get_rdatalen(rr, len, dname_len))+2;
+
+       labs = dname_count_labels(rr);
+
+       rr_class = sldns_wirerr_get_class(rr, len, dname_len);
+       rr_type = sldns_wirerr_get_type(rr, len, dname_len);
+
+       z = local_zones_lookup(local_zones, rr, dname_len,
+                       labs, rr_class, rr_type);
+       if (!z) {
+               ssl_printf(ssl, "error no zone for rr %s\n", arg);
+               return 0;
+       }
+
+       ld = local_zone_find_data(z, rr, dname_len, labs);
+       if (!ld) {
+               ssl_printf(ssl, "error no local data for rr %s\n", arg);
+               return 0;
+       }
+
+       struct local_rrset* prev=NULL, *p=ld->rrsets;
+       while (p && ntohs(p->rrset->rk.type) != rr_type) {
+               prev = p;
+               p = p->next;
+       }
+
+       if (!p) {
+               ssl_printf(ssl, "error no rrset for rr %s\n", arg);
+               return 0;
+    }
+
+       d = (struct packed_rrset_data*)p->rrset->entry.data;
+       if (!packed_rrset_find_rr(d, rdata, rdata_len, &index)) {
+               ssl_printf(ssl, "error rr %s not found in rrset\n", arg);
+               return 0;
+       }
+
+       if (!local_rrset_remove_rr(d, index)) {
+               ssl_printf(ssl, "error unable to delete rr %s\n", arg);
+               return 0;
+       }
+
+       return 1;
+}
+
 /** Remove RR data */
 static int
 perform_data_remove(RES* ssl, struct local_zones* zones, char* arg)
 {
-       uint8_t* nm;
-       int nmlabs;
-       size_t nmlen;
-       if(!parse_arg_name(ssl, arg, &nm, &nmlen, &nmlabs))
+       uint8_t rr[LDNS_RR_BUF_SIZE], *nm;
+       size_t len = sizeof(rr);
+       int status, nmlabs;
+       size_t nmlen, dname_len;
+
+       /* try to parse as a rr first */
+       status = sldns_str2wire_rr_buf(arg, rr, &len, &dname_len, 3600,
+                               NULL, 0, NULL, 0);
+
+       /* try to parse as a domain name second */
+       if (status != 0) {
+               if (parse_arg_name(ssl, arg, &nm, &nmlen, &nmlabs)) {
+                       local_zones_del_data(zones, nm,
+                               nmlen, nmlabs, LDNS_RR_CLASS_IN);
+                       free(nm);
+                       return 1;
+               }
+               ssl_printf(ssl, "error cannot parse rr %s at %d: %s\n", arg,
+                       LDNS_WIREPARSE_OFFSET(status),
+                       sldns_get_errorstr_parse(status));
                return 0;
-       local_zones_del_data(zones, nm,
-               nmlen, nmlabs, LDNS_RR_CLASS_IN);
-       free(nm);
+       }
+
+       /* handle the rr case */
+       if (!perform_data_remove_rr(ssl, zones, rr, len, dname_len, arg))
+               return 0;
+
        return 1;
 }