Forgot to include util/allow_response_list.[ch]

diff --git a/util/allow_response_list.c b/util/allow_response_list.c
new file mode 100644 (file)
index 0000000..ef1ae1e
--- /dev/null
+++ b/util/allow_response_list.c
@@ -0,0 +1,181 @@
+/*
+ * util/allow_response_list.c - allow response list storage for the server.
+ *
+ * Copyright (c) 2025, NLnet Labs. All rights reserved.
+ *
+ * This software is open source.
+ * 
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 
+ * Neither the name of the NLNET LABS nor the names of its contributors may
+ * be used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * \file
+ *
+ * This file helps the server discard excess TCP connections.
+ */
+#include "config.h"
+#include "util/regional.h"
+#include "util/log.h"
+#include "util/config_file.h"
+#include "util/net_help.h"
+#include "util/allow_response_list.h"
+#include "services/localzone.h"
+#include "sldns/str2wire.h"
+
+const char* TSIG_NOKEY   = "NOKEY";
+const char* TSIG_BLOCKED = "BLOCKED";
+
+struct arl_list*
+arl_list_create(void)
+{
+       struct arl_list* arl = (struct arl_list*)calloc(1,
+               sizeof(struct arl_list));
+       if(!arl)
+               return NULL;
+       arl->region = regional_create();
+       if(!arl->region) {
+               arl_list_delete(arl);
+               return NULL;
+       }
+       return arl;
+}
+
+static void
+arl_list_free_node(rbnode_type* node, void* ATTR_UNUSED(arg))
+{
+       struct arl_addr* n = (struct arl_addr*) node;
+#ifdef THREADS_DISABLED
+       (void)n;
+#endif
+}
+
+void
+arl_list_delete(struct arl_list* arl)
+{
+       if(!arl)
+               return;
+       traverse_postorder(&arl->tree, arl_list_free_node, NULL);
+       regional_destroy(arl->region);
+       free(arl);
+}
+
+/** insert new address into arl_list structure */
+static struct arl_addr*
+arl_list_insert(struct arl_list* arl, struct sockaddr_storage* addr,
+       socklen_t addrlen, int net, const char* tsig_key_name,
+       int complain_duplicates)
+{
+       struct arl_addr* node = regional_alloc_zero(arl->region,
+               sizeof(struct arl_addr));
+       if(!node)
+               return NULL;
+       if(!tsig_key_name)
+              ;
+       else if(strcmp(tsig_key_name, TSIG_NOKEY) == 0)
+               node->tsig_key_name = TSIG_NOKEY;
+       else if(strcmp(tsig_key_name, TSIG_BLOCKED) == 0)
+               node->tsig_key_name = TSIG_BLOCKED;
+       else
+               node->tsig_key_name = tsig_key_name;
+       if(!addr_tree_insert(&arl->tree, &node->node, addr, addrlen, net)) {
+               if(complain_duplicates)
+                       verbose(VERB_QUERY, "duplicate arl address ignored.");
+       }
+       return node;
+}
+
+/** apply arl_list string */
+static int
+arl_list_str_cfg(struct arl_list* arl, const char* str, const char* s2,
+       int complain_duplicates)
+{
+       struct sockaddr_storage addr;
+       int net;
+       socklen_t addrlen;
+       if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) {
+               log_err("cannot parse allow response netblock: %s", str);
+               return 0;
+       }
+       if(!arl_list_insert(arl, &addr, addrlen, net, s2,
+               complain_duplicates)) {
+               log_err("out of memory");
+               return 0;
+       }
+       return 1;
+}
+
+/** read arl_list config */
+static int
+read_arl_list(struct arl_list* arl, struct config_file* cfg)
+{
+       struct config_str2list* p;
+       for(p = cfg->allow_response_list; p; p = p->next) {
+               log_assert(p->str && p->str2);
+               if(!arl_list_str_cfg(arl, p->str, p->str2, 1))
+                       return 0;
+       }
+       return 1;
+}
+
+int
+arl_list_apply_cfg(struct arl_list* arl, struct config_file* cfg)
+{
+       regional_free_all(arl->region);
+       addr_tree_init(&arl->tree);
+       if(!read_arl_list(arl, cfg))
+               return 0;
+       addr_tree_init_parents(&arl->tree);
+       return 1;
+}
+
+struct arl_addr*
+arl_addr_lookup(struct arl_list* arl, struct sockaddr_storage* addr,
+        socklen_t addrlen)
+{
+       return (struct arl_addr*)addr_tree_lookup(&arl->tree,
+               addr, addrlen);
+}
+
+size_t
+arl_list_get_mem(struct arl_list* arl)
+{
+       if(!arl) return 0;
+       return sizeof(*arl) + regional_get_mem(arl->region);
+}
+
+void arl_list_swap_tree(struct arl_list* arl, struct arl_list* data)
+{
+       /* swap tree and region */
+       rbtree_type oldtree = arl->tree;
+       struct regional* oldregion = arl->region;
+       arl->tree = data->tree;
+       arl->region = data->region;
+       data->tree = oldtree;
+       data->region = oldregion;
+}
+

diff --git a/util/allow_response_list.h b/util/allow_response_list.h
new file mode 100644 (file)
index 0000000..14c9344
--- /dev/null
+++ b/util/allow_response_list.h
@@ -0,0 +1,123 @@
+/*
+ * util/allow_response_list.h - allow-response list storage for the server.
+ *
+ * Copyright (c) 2025, NLnet Labs. All rights reserved.
+ *
+ * This software is open source.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of the NLNET LABS nor the names of its contributors may
+ * be used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * \file
+ *
+ * This file keeps track of the list of clients that are allowed to send
+ * responses to the server, so the server can store it in the cache.
+ */
+
+#ifndef UTIL_ALLOW_RESPONSE_LIST_H
+#define UTIL_ALLOW_RESPONSE_LIST_H
+#include "util/storage/dnstree.h"
+#include "util/locks.h"
+struct config_file;
+struct regional;
+
+/**
+ * allow response list storage structure
+ */
+struct arl_list {
+       /** regional for allocation */
+       struct regional* region;
+       /**
+        * Tree of the addresses that are allowed to send responses.
+        * contents of type arl_addr.
+        */
+       rbtree_type tree;
+};
+
+extern const char* TSIG_NOKEY;
+extern const char* TSIG_BLOCKED;
+
+/**
+ *
+ * An address span that is allowed to send responses
+ */
+struct arl_addr {
+       /** node in address tree */
+       struct addr_tree_node node;
+       /** tsig key name, NULL means no key needed */
+       const char* tsig_key_name;
+};
+
+/**
+ * Create allow response list structure
+ * @return new structure or NULL on error.
+ */
+struct arl_list* arl_list_create(void);
+
+/**
+ * Delete allow response list  structure.
+ * @param arl: to delete.
+ */
+void arl_list_delete(struct arl_list* arl);
+
+/**
+ * Process allow response list config.
+ * @param arl: where to store.
+ * @param cfg: config options.
+ * @return 0 on error.
+ */
+int arl_list_apply_cfg(struct arl_list* arl, struct config_file* cfg);
+
+/**
+ * Lookup address to see its allow response list structure
+ * @param arl: structure for address storage.
+ * @param addr: address to check
+ * @param addrlen: length of addr.
+ * @return: arl structure from this address.
+ */
+struct arl_addr*
+arl_addr_lookup(struct arl_list* arl, struct sockaddr_storage* addr,
+        socklen_t addrlen);
+
+/**
+ * Get memory used by allow response list structure.
+ * @param arl: structure for address storage.
+ * @return bytes in use.
+ */
+size_t arl_list_get_mem(struct arl_list* arl);
+
+/**
+ * Swap internal tree with preallocated entries.
+ * @param arl: the allow response list structure.
+ * @param data: the data structure used to take elements from. This contains
+ *     the old elements on return.
+ */
+void arl_list_swap_tree(struct arl_list* arl, struct arl_list* data);
+
+#endif /* UTIL_TCP_CONN_LIMIT_H */