/* * daemon/acl_list.h - client access control storage for the server. * * Copyright (c) 2007, 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 keep out queries from outside sources, that * should not be answered. */ #include "config.h" #include "daemon/acl_list.h" #include "util/regional.h" #include "util/log.h" #include "util/config_file.h" #include "util/net_help.h" #include "services/localzone.h" #include "sldns/str2wire.h" struct acl_list* acl_list_create(void) { struct acl_list* acl = (struct acl_list*)calloc(1, sizeof(struct acl_list)); if(!acl) return NULL; acl->region = regional_create(); if(!acl->region) { acl_list_delete(acl); return NULL; } return acl; } void acl_list_delete(struct acl_list* acl) { if(!acl) return; regional_destroy(acl->region); free(acl); } /** insert new address into acl_list structure */ static struct acl_addr* acl_list_insert(struct acl_list* acl, struct sockaddr_storage* addr, socklen_t addrlen, int net, enum acl_access control, int complain_duplicates) { struct acl_addr* node = regional_alloc_zero(acl->region, sizeof(struct acl_addr)); if(!node) return NULL; node->control = control; if(!addr_tree_insert(&acl->tree, &node->node, addr, addrlen, net)) { if(complain_duplicates) verbose(VERB_QUERY, "duplicate acl address ignored."); } return node; } /** apply acl_list string */ static int acl_list_str_cfg(struct acl_list* acl, const char* str, const char* s2, int complain_duplicates) { struct sockaddr_storage addr; int net; socklen_t addrlen; enum acl_access control; if(strcmp(s2, "allow") == 0) control = acl_allow; else if(strcmp(s2, "deny") == 0) control = acl_deny; else if(strcmp(s2, "refuse") == 0) control = acl_refuse; else if(strcmp(s2, "deny_non_local") == 0) control = acl_deny_non_local; else if(strcmp(s2, "refuse_non_local") == 0) control = acl_refuse_non_local; else if(strcmp(s2, "allow_snoop") == 0) control = acl_allow_snoop; else if(strcmp(s2, "allow_setrd") == 0) control = acl_allow_setrd; else { log_err("access control type %s unknown", str); return 0; } if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) { log_err("cannot parse access control: %s %s", str, s2); return 0; } if(!acl_list_insert(acl, &addr, addrlen, net, control, complain_duplicates)) { log_err("out of memory"); return 0; } return 1; } /** find or create node (NULL on parse or error) */ static struct acl_addr* acl_find_or_create(struct acl_list* acl, const char* str) { struct acl_addr* node; struct sockaddr_storage addr; int net; socklen_t addrlen; if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) { log_err("cannot parse netblock: %s", str); return NULL; } /* find or create node */ if(!(node=(struct acl_addr*)addr_tree_find(&acl->tree, &addr, addrlen, net))) { /* create node, type 'allow' since otherwise tags are * pointless, can override with specific access-control: cfg */ if(!(node=(struct acl_addr*)acl_list_insert(acl, &addr, addrlen, net, acl_allow, 1))) { log_err("out of memory"); return NULL; } } return node; } /** apply acl_tag string */ static int acl_list_tags_cfg(struct acl_list* acl, const char* str, uint8_t* bitmap, size_t bitmaplen) { struct acl_addr* node; if(!(node=acl_find_or_create(acl, str))) return 0; node->taglen = bitmaplen; node->taglist = regional_alloc_init(acl->region, bitmap, bitmaplen); if(!node->taglist) { log_err("out of memory"); return 0; } return 1; } /** apply acl_view string */ static int acl_list_view_cfg(struct acl_list* acl, const char* str, const char* str2, struct views* vs) { struct acl_addr* node; if(!(node=acl_find_or_create(acl, str))) return 0; node->view = views_find_view(vs, str2, 0 /* get read lock*/); if(!node->view) { log_err("no view with name: %s", str2); return 0; } lock_rw_unlock(&node->view->lock); return 1; } /** apply acl_tag_action string */ static int acl_list_tag_action_cfg(struct acl_list* acl, struct config_file* cfg, const char* str, const char* tag, const char* action) { struct acl_addr* node; int tagid; enum localzone_type t; if(!(node=acl_find_or_create(acl, str))) return 0; /* allocate array if not yet */ if(!node->tag_actions) { node->tag_actions = (uint8_t*)regional_alloc_zero(acl->region, sizeof(*node->tag_actions)*cfg->num_tags); if(!node->tag_actions) { log_err("out of memory"); return 0; } node->tag_actions_size = (size_t)cfg->num_tags; } /* parse tag */ if((tagid=find_tag_id(cfg, tag)) == -1) { log_err("cannot parse tag (define-tag it): %s %s", str, tag); return 0; } if((size_t)tagid >= node->tag_actions_size) { log_err("tagid too large for array %s %s", str, tag); return 0; } if(!local_zone_str2type(action, &t)) { log_err("cannot parse access control action type: %s %s %s", str, tag, action); return 0; } node->tag_actions[tagid] = (uint8_t)t; return 1; } /** check wire data parse */ static int check_data(const char* data, const struct config_strlist* head) { char buf[65536]; uint8_t rr[LDNS_RR_BUF_SIZE]; size_t len = sizeof(rr); int res; /* '.' is sufficient for validation, and it makes the call to * sldns_wirerr_get_type() simpler below. */ snprintf(buf, sizeof(buf), "%s %s", ".", data); res = sldns_str2wire_rr_buf(buf, rr, &len, NULL, 3600, NULL, 0, NULL, 0); /* Reject it if we would end up having CNAME and other data (including * another CNAME) for the same tag. */ if(res == 0 && head) { const char* err_data = NULL; if(sldns_wirerr_get_type(rr, len, 1) == LDNS_RR_TYPE_CNAME) { /* adding CNAME while other data already exists. */ err_data = data; } else { snprintf(buf, sizeof(buf), "%s %s", ".", head->str); len = sizeof(rr); res = sldns_str2wire_rr_buf(buf, rr, &len, NULL, 3600, NULL, 0, NULL, 0); if(res != 0) { /* This should be impossible here as head->str * has been validated, but we check it just in * case. */ return 0; } if(sldns_wirerr_get_type(rr, len, 1) == LDNS_RR_TYPE_CNAME) /* already have CNAME */ err_data = head->str; } if(err_data) { log_err("redirect tag data '%s' must not coexist with " "other data.", err_data); return 0; } } if(res == 0) return 1; log_err("rr data [char %d] parse error %s", (int)LDNS_WIREPARSE_OFFSET(res)-2, sldns_get_errorstr_parse(res)); return 0; } /** apply acl_tag_data string */ static int acl_list_tag_data_cfg(struct acl_list* acl, struct config_file* cfg, const char* str, const char* tag, const char* data) { struct acl_addr* node; int tagid; char* dupdata; if(!(node=acl_find_or_create(acl, str))) return 0; /* allocate array if not yet */ if(!node->tag_datas) { node->tag_datas = (struct config_strlist**)regional_alloc_zero( acl->region, sizeof(*node->tag_datas)*cfg->num_tags); if(!node->tag_datas) { log_err("out of memory"); return 0; } node->tag_datas_size = (size_t)cfg->num_tags; } /* parse tag */ if((tagid=find_tag_id(cfg, tag)) == -1) { log_err("cannot parse tag (define-tag it): %s %s", str, tag); return 0; } if((size_t)tagid >= node->tag_datas_size) { log_err("tagid too large for array %s %s", str, tag); return 0; } /* check data? */ if(!check_data(data, node->tag_datas[tagid])) { log_err("cannot parse access-control-tag data: %s %s '%s'", str, tag, data); return 0; } dupdata = regional_strdup(acl->region, data); if(!dupdata) { log_err("out of memory"); return 0; } if(!cfg_region_strlist_insert(acl->region, &(node->tag_datas[tagid]), dupdata)) { log_err("out of memory"); return 0; } return 1; } /** read acl_list config */ static int read_acl_list(struct acl_list* acl, struct config_file* cfg) { struct config_str2list* p; for(p = cfg->acls; p; p = p->next) { log_assert(p->str && p->str2); if(!acl_list_str_cfg(acl, p->str, p->str2, 1)) return 0; } return 1; } /** read acl tags config */ static int read_acl_tags(struct acl_list* acl, struct config_file* cfg) { struct config_strbytelist* np, *p = cfg->acl_tags; cfg->acl_tags = NULL; while(p) { log_assert(p->str && p->str2); if(!acl_list_tags_cfg(acl, p->str, p->str2, p->str2len)) { config_del_strbytelist(p); return 0; } /* free the items as we go to free up memory */ np = p->next; free(p->str); free(p->str2); free(p); p = np; } return 1; } /** read acl view config */ static int read_acl_view(struct acl_list* acl, struct config_file* cfg, struct views* v) { struct config_str2list* np, *p = cfg->acl_view; cfg->acl_view = NULL; while(p) { log_assert(p->str && p->str2); if(!acl_list_view_cfg(acl, p->str, p->str2, v)) { return 0; } /* free the items as we go to free up memory */ np = p->next; free(p->str); free(p->str2); free(p); p = np; } return 1; } /** read acl tag actions config */ static int read_acl_tag_actions(struct acl_list* acl, struct config_file* cfg) { struct config_str3list* p, *np; p = cfg->acl_tag_actions; cfg->acl_tag_actions = NULL; while(p) { log_assert(p->str && p->str2 && p->str3); if(!acl_list_tag_action_cfg(acl, cfg, p->str, p->str2, p->str3)) { config_deltrplstrlist(p); return 0; } /* free the items as we go to free up memory */ np = p->next; free(p->str); free(p->str2); free(p->str3); free(p); p = np; } return 1; } /** read acl tag datas config */ static int read_acl_tag_datas(struct acl_list* acl, struct config_file* cfg) { struct config_str3list* p, *np; p = cfg->acl_tag_datas; cfg->acl_tag_datas = NULL; while(p) { log_assert(p->str && p->str2 && p->str3); if(!acl_list_tag_data_cfg(acl, cfg, p->str, p->str2, p->str3)) { config_deltrplstrlist(p); return 0; } /* free the items as we go to free up memory */ np = p->next; free(p->str); free(p->str2); free(p->str3); free(p); p = np; } return 1; } int acl_list_apply_cfg(struct acl_list* acl, struct config_file* cfg, struct views* v) { regional_free_all(acl->region); addr_tree_init(&acl->tree); if(!read_acl_list(acl, cfg)) return 0; if(!read_acl_view(acl, cfg, v)) return 0; if(!read_acl_tags(acl, cfg)) return 0; if(!read_acl_tag_actions(acl, cfg)) return 0; if(!read_acl_tag_datas(acl, cfg)) return 0; /* insert defaults, with '0' to ignore them if they are duplicates */ if(!acl_list_str_cfg(acl, "0.0.0.0/0", "refuse", 0)) return 0; if(!acl_list_str_cfg(acl, "127.0.0.0/8", "allow", 0)) return 0; if(cfg->do_ip6) { if(!acl_list_str_cfg(acl, "::0/0", "refuse", 0)) return 0; if(!acl_list_str_cfg(acl, "::1", "allow", 0)) return 0; if(!acl_list_str_cfg(acl, "::ffff:127.0.0.1", "allow", 0)) return 0; } addr_tree_init_parents(&acl->tree); return 1; } enum acl_access acl_get_control(struct acl_addr* acl) { if(acl) return acl->control; return acl_deny; } struct acl_addr* acl_addr_lookup(struct acl_list* acl, struct sockaddr_storage* addr, socklen_t addrlen) { return (struct acl_addr*)addr_tree_lookup(&acl->tree, addr, addrlen); } size_t acl_list_get_mem(struct acl_list* acl) { if(!acl) return 0; return sizeof(*acl) + regional_get_mem(acl->region); } const char* acl_access_to_str(enum acl_access acl) { switch(acl) { case acl_deny: return "deny"; case acl_refuse: return "refuse"; case acl_deny_non_local: return "deny_non_local"; case acl_refuse_non_local: return "refuse_non_local"; case acl_allow: return "allow"; case acl_allow_snoop: return "allow_snoop"; case acl_allow_setrd: return "allow_setrd"; default: break; } return "unknown"; } void log_acl_action(const char* action, struct sockaddr_storage* addr, socklen_t addrlen, enum acl_access acl, struct acl_addr* acladdr) { char a[128], n[128]; uint16_t port; addr_to_str(addr, addrlen, a, sizeof(a)); port = ntohs(((struct sockaddr_in*)addr)->sin_port); if(acladdr) { addr_to_str(&acladdr->node.addr, acladdr->node.addrlen, n, sizeof(n)); verbose(VERB_ALGO, "%s query from %s port %d because of " "%s/%d %s", action, a, (int)port, n, acladdr->node.net, acl_access_to_str(acl)); } else { verbose(VERB_ALGO, "%s query from %s port %d", action, a, (int)port); } }