s4 dns: Add a prerequisites check for updates

diff --git a/source4/dns_server/dns_update.c b/source4/dns_server/dns_update.c
index 4cd940ed10665ddd58c07ed591f384c874d82ea3..72944730a6f2a6a5c2c64bab8808614213443c52 100644 (file)
--- a/source4/dns_server/dns_update.c
+++ b/source4/dns_server/dns_update.c
@@ -29,6 +29,67 @@
 #include "dsdb/common/util.h"
 #include "dns_server/dns_server.h"
 
+static WERROR check_prerequsites(struct dns_server *dns,
+                                TALLOC_CTX *mem_ctx,
+                                const struct dns_name_packet *in,
+                                const struct dns_res_rec *prereqs, uint16_t count)
+{
+       const struct dns_name_question *zone;
+       size_t host_part_len = 0;
+       uint16_t i;
+
+       zone = in->questions;
+
+       for (i = 0; i < count; i++) {
+               const struct dns_res_rec *r = &prereqs[i];
+               bool match;
+
+               if (r->ttl != 0) {
+                       return DNS_ERR(FORMAT_ERROR);
+               }
+               match = dns_name_match(zone->name, r->name, &host_part_len);
+               if (!match) {
+                       /* TODO: check if we need to echo all prereqs if the
+                        * first fails */
+                       return DNS_ERR(NOTZONE);
+               }
+               if (r->rr_class == DNS_QCLASS_ANY) {
+                       if (r->length != 0) {
+                               return DNS_ERR(FORMAT_ERROR);
+                       }
+                       if (r->rr_type == DNS_QTYPE_ALL) {
+                               /* TODO: Check if zone has at least one RR */
+                               return DNS_ERR(NAME_ERROR);
+                       } else {
+                               /* TODO: Check if RR exists of the specified type */
+                               return DNS_ERR(NXRRSET);
+                       }
+                       continue;
+               }
+               if (r->rr_class == DNS_QCLASS_NONE) {
+                       if (r->length != 0) {
+                               return DNS_ERR(FORMAT_ERROR);
+                       }
+                       if (r->rr_type == DNS_QTYPE_ALL) {
+                               /* TODO: Return this error if the given name exits in this zone */
+                               return DNS_ERR(YXDOMAIN);
+                       } else {
+                               /* TODO: Return error if there's an RRset of this type in the zone */
+                               return DNS_ERR(YXRRSET);
+                       }
+                       continue;
+               }
+               if (r->rr_class == zone->question_class) {
+                       /* Check if there's a RR with this */
+                       return DNS_ERR(NOT_IMPLEMENTED);
+               } else {
+                       return DNS_ERR(FORMAT_ERROR);
+               }
+       }
+
+
+       return WERR_OK;
+}
 
 WERROR dns_server_process_update(struct dns_server *dns,
                                 TALLOC_CTX *mem_ctx,
@@ -40,7 +101,7 @@ WERROR dns_server_process_update(struct dns_server *dns,
        struct dns_name_question *zone;
        const struct dns_server_zone *z;
        size_t host_part_len = 0;
-       uint16_t i;
+       WERROR werror = WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED;
 
        if (in->qdcount != 1) {
                return DNS_ERR(FORMAT_ERROR);
@@ -68,8 +129,12 @@ WERROR dns_server_process_update(struct dns_server *dns,
        }
 
        if (host_part_len != 0) {
+               /* TODO: We need to delegate this one */
                return DNS_ERR(NOT_IMPLEMENTED);
        }
 
-       return DNS_ERR(NOT_IMPLEMENTED);
+       werror = check_prerequsites(dns, mem_ctx, in, prereqs, prereq_count);
+       W_ERROR_NOT_OK_RETURN(werror);
+
+       return werror;
 }