1 /* 2 * pythonmod_utils.c: utilities used by wrapper 3 * 4 * Copyright (c) 2009, Zdenek Vasicek (vasicek AT fit.vutbr.cz) 5 * Marek Vavrusa (xvavru00 AT stud.fit.vutbr.cz) 6 * 7 * This software is open source. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 13 * * Redistributions of source code must retain the above copyright notice, 14 * this list of conditions and the following disclaimer. 15 * 16 * * Redistributions in binary form must reproduce the above copyright notice, 17 * this list of conditions and the following disclaimer in the documentation 18 * and/or other materials provided with the distribution. 19 * 20 * * Neither the name of the organization nor the names of its 21 * contributors may be used to endorse or promote products derived from this 22 * software without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 25 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 26 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 27 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE 28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 * POSSIBILITY OF SUCH DAMAGE. 35 */ 36 /** 37 * \file 38 * Utility functions for the python module that perform stores and loads and 39 * conversions. 40 */ 41 #include "config.h" 42 #include "util/module.h" 43 #include "util/netevent.h" 44 #include "util/net_help.h" 45 #include "services/cache/dns.h" 46 #include "services/cache/rrset.h" 47 #include "util/data/msgparse.h" 48 #include "util/data/msgreply.h" 49 #include "util/storage/slabhash.h" 50 #include "util/regional.h" 51 #include "iterator/iter_delegpt.h" 52 #include "sldns/sbuffer.h" 53 54 #undef _POSIX_C_SOURCE 55 #undef _XOPEN_SOURCE 56 #include <Python.h> 57 58 /* Store the reply_info and query_info pair in message cache (qstate->msg_cache) */ 59 int storeQueryInCache(struct module_qstate* qstate, struct query_info* qinfo, struct reply_info* msgrep, int is_referral) 60 { 61 if (!msgrep) 62 return 0; 63 64 if (msgrep->authoritative) /*authoritative answer can't be stored in cache*/ 65 { 66 PyErr_SetString(PyExc_ValueError, "Authoritative answer can't be stored"); 67 return 0; 68 } 69 70 return dns_cache_store(qstate->env, qinfo, msgrep, is_referral, 71 qstate->prefetch_leeway, 0, NULL, qstate->query_flags); 72 } 73 74 /* Invalidate the message associated with query_info stored in message cache */ 75 void invalidateQueryInCache(struct module_qstate* qstate, struct query_info* qinfo) 76 { 77 hashvalue_type h; 78 struct lruhash_entry* e; 79 struct reply_info *r; 80 size_t i, j; 81 82 h = query_info_hash(qinfo, qstate->query_flags); 83 if ((e=slabhash_lookup(qstate->env->msg_cache, h, qinfo, 0))) 84 { 85 r = (struct reply_info*)(e->data); 86 if (r) 87 { 88 r->ttl = 0; 89 if(rrset_array_lock(r->ref, r->rrset_count, *qstate->env->now)) { 90 for(i=0; i< r->rrset_count; i++) 91 { 92 struct packed_rrset_data* data = 93 (struct packed_rrset_data*) r->ref[i].key->entry.data; 94 if(i>0 && r->ref[i].key == r->ref[i-1].key) 95 continue; 96 97 data->ttl = r->ttl; 98 for(j=0; j<data->count + data->rrsig_count; j++) 99 data->rr_ttl[j] = r->ttl; 100 } 101 rrset_array_unlock(r->ref, r->rrset_count); 102 } 103 } 104 lock_rw_unlock(&e->lock); 105 } else { 106 log_info("invalidateQueryInCache: qinfo is not in cache"); 107 } 108 } 109 110 /* Create response according to the ldns packet content */ 111 int createResponse(struct module_qstate* qstate, sldns_buffer* pkt) 112 { 113 struct msg_parse* prs; 114 struct edns_data edns; 115 116 /* parse message */ 117 prs = (struct msg_parse*) regional_alloc(qstate->env->scratch, sizeof(struct msg_parse)); 118 if (!prs) { 119 log_err("storeResponse: out of memory on incoming message"); 120 return 0; 121 } 122 123 memset(prs, 0, sizeof(*prs)); 124 memset(&edns, 0, sizeof(edns)); 125 126 sldns_buffer_set_position(pkt, 0); 127 if (parse_packet(pkt, prs, qstate->env->scratch) != LDNS_RCODE_NOERROR) { 128 verbose(VERB_ALGO, "storeResponse: parse error on reply packet"); 129 return 0; 130 } 131 /* edns is not examined, but removed from message to help cache */ 132 if(parse_extract_edns(prs, &edns, qstate->env->scratch) != 133 LDNS_RCODE_NOERROR) 134 return 0; 135 136 /* remove CD-bit, we asked for in case we handle validation ourself */ 137 prs->flags &= ~BIT_CD; 138 139 /* allocate response dns_msg in region */ 140 qstate->return_msg = (struct dns_msg*)regional_alloc(qstate->region, sizeof(struct dns_msg)); 141 if (!qstate->return_msg) 142 return 0; 143 144 memset(qstate->return_msg, 0, sizeof(*qstate->return_msg)); 145 if(!parse_create_msg(pkt, prs, NULL, &(qstate->return_msg)->qinfo, &(qstate->return_msg)->rep, qstate->region)) { 146 log_err("storeResponse: malloc failure: allocating incoming dns_msg"); 147 return 0; 148 } 149 150 /* Make sure that the RA flag is set (since the presence of 151 * this module means that recursion is available) */ 152 /* qstate->return_msg->rep->flags |= BIT_RA; */ 153 154 /* Clear the AA flag */ 155 /* FIXME: does this action go here or in some other module? */ 156 /*qstate->return_msg->rep->flags &= ~BIT_AA; */ 157 158 /* make sure QR flag is on */ 159 /*qstate->return_msg->rep->flags |= BIT_QR; */ 160 161 if(verbosity >= VERB_ALGO) 162 log_dns_msg("storeResponse: packet:", &qstate->return_msg->qinfo, qstate->return_msg->rep); 163 164 return 1; 165 } 166 167 168 /* Convert reply->addr to string */ 169 void reply_addr2str(struct comm_reply* reply, char* dest, int maxlen) 170 { 171 int af = (int)((struct sockaddr_in*) &(reply->addr))->sin_family; 172 void* sinaddr = &((struct sockaddr_in*) &(reply->addr))->sin_addr; 173 174 if(af == AF_INET6) 175 sinaddr = &((struct sockaddr_in6*)&(reply->addr))->sin6_addr; 176 dest[0] = 0; 177 if (inet_ntop(af, sinaddr, dest, (socklen_t)maxlen) == 0) 178 return; 179 dest[maxlen-1] = 0; 180 } 181 182 /* Convert target->addr to string */ 183 void delegpt_addr_addr2str(struct delegpt_addr* target, char *dest, int maxlen) 184 { 185 int af = (int)((struct sockaddr_in*) &(target->addr))->sin_family; 186 void* sinaddr = &((struct sockaddr_in*) &(target->addr))->sin_addr; 187 188 if(af == AF_INET6) 189 sinaddr = &((struct sockaddr_in6*)&(target->addr))->sin6_addr; 190 dest[0] = 0; 191 if (inet_ntop(af, sinaddr, dest, (socklen_t)maxlen) == 0) 192 return; 193 dest[maxlen-1] = 0; 194 } 195